class PGconn
The PostgreSQL connection class. The interface for this class is based on libpq, the C application programmer's interface to PostgreSQL. Some familiarity with libpq is recommended, but not necessary.
For example, to send query to the database on the localhost:
require 'pg' conn = PG::Connection.open(:dbname => 'test') res = conn.exec_params('SELECT $1 AS a, $2 AS b, $3 AS c', [1, 2, nil]) # Equivalent to: # res = conn.exec('SELECT 1 AS a, 2 AS b, NULL AS c')
See the PG::Result class for information on working with the results of a query.
Constants
- CONNECT_ARGUMENT_ORDER
The order the options are passed to the ::connect method.
Public Class Methods
Returns an array of hashes. Each hash has the keys:
- :keyword
-
the name of the option
- :envvar
-
the environment variable to fall back to
- :compiled
-
the compiled in option as a secondary fallback
- :val
-
the option's current value, or
nil
if not known - :label
-
the label for the field
- :dispchar
-
“” for normal, “D” for debug, and “*” for password
- :dispsize
-
field size
static VALUE pgconn_s_conndefaults(VALUE self) { PQconninfoOption *options = PQconndefaults(); VALUE array = pgconn_make_conninfo_array( options ); PQconninfoFree(options); UNUSED( self ); return array; }
Return the Postgres connection defaults structure as a Hash keyed by option keyword (as a Symbol).
See also conndefaults
# File lib/pg/connection.rb, line 201 def self.conndefaults_hash return self.conndefaults.each_with_object({}) do |info, hash| hash[ info[:keyword].to_sym ] = info[:val] end end
This is an asynchronous version of PG::Connection.connect().
Use connect_poll to poll the status of the connection.
NOTE: this does not set the connection's
client_encoding
for you if Encoding.default_internal is set.
To set it after the connection is established, call internal_encoding=.
You can also set it automatically by setting ENV, or include the 'options'
connection parameter.
static VALUE pgconn_s_connect_start( int argc, VALUE *argv, VALUE klass ) { VALUE rb_conn; VALUE conninfo; VALUE error; t_pg_connection *this; /* * PG::Connection.connect_start must act as both alloc() and initialize() * because it is not invoked by calling new(). */ rb_conn = pgconn_s_allocate( klass ); this = pg_get_connection( rb_conn ); conninfo = rb_funcall2( klass, rb_intern("parse_connect_args"), argc, argv ); this->pgconn = gvl_PQconnectStart( StringValueCStr(conninfo) ); if( this->pgconn == NULL ) rb_raise(rb_ePGerror, "PQconnectStart() unable to allocate structure"); if ( PQstatus(this->pgconn) == CONNECTION_BAD ) { error = rb_exc_new2(rb_eConnectionBad, PQerrorMessage(this->pgconn)); rb_iv_set(error, "@connection", rb_conn); rb_exc_raise(error); } if ( rb_block_given_p() ) { return rb_ensure( rb_yield, rb_conn, pgconn_finish, rb_conn ); } return rb_conn; }
This function is intended to be used by client applications that send commands like: +ALTER USER joe PASSWORD 'pwd'+. The arguments are the cleartext password, and the SQL name of the user it is for.
Return value is the encrypted password.
static VALUE pgconn_s_encrypt_password(VALUE self, VALUE password, VALUE username) { char *encrypted = NULL; VALUE rval = Qnil; UNUSED( self ); Check_Type(password, T_STRING); Check_Type(username, T_STRING); encrypted = PQencryptPassword(StringValueCStr(password), StringValueCStr(username)); rval = rb_str_new2( encrypted ); PQfreemem( encrypted ); OBJ_INFECT( rval, password ); OBJ_INFECT( rval, username ); return rval; }
Connection instance method for versions of 8.1 and higher of libpq uses PQescapeByteaConn, which is safer. Avoid calling as a class method, the class method uses the deprecated PQescapeBytea() API function.
Use the instance method version of this function, it is safer than the class method.
Escapes binary data for use within an SQL command with the type
bytea
.
Certain byte values must be escaped (but all byte values may be escaped)
when used as part of a bytea
literal in an SQL statement. In
general, to escape a byte, it is converted into the three digit octal
number equal to the octet value, and preceded by two backslashes. The
single quote (') and backslash () characters have special alternative
escape sequences. escape_bytea performs this
operation, escaping only the minimally required bytes.
Consider using #exec_params, which avoids the need for passing values inside of SQL commands.
static VALUE pgconn_s_escape_bytea(VALUE self, VALUE str) { unsigned char *from, *to; size_t from_len, to_len; VALUE ret; Check_Type(str, T_STRING); from = (unsigned char*)RSTRING_PTR(str); from_len = RSTRING_LEN(str); if ( rb_obj_is_kind_of(self, rb_cPGconn) ) { to = PQescapeByteaConn(pg_get_pgconn(self), from, from_len, &to_len); } else { to = PQescapeBytea( from, from_len, &to_len); } ret = rb_str_new((char*)to, to_len - 1); OBJ_INFECT(ret, str); PQfreemem(to); return ret; }
Connection instance method for versions of 8.1 and higher of libpq uses PQescapeStringConn, which is safer. Avoid calling as a class method, the class method uses the deprecated PQescapeString() API function.
Returns a SQL-safe version of the String str. This is the preferred way to make strings safe for inclusion in SQL queries.
Consider using #exec_params, which avoids the need for passing values inside of SQL commands.
Encoding of escaped string will be equal to client encoding of connection.
static VALUE pgconn_s_escape(VALUE self, VALUE string) { char *escaped; size_t size; int error; VALUE result; Check_Type(string, T_STRING); escaped = ALLOC_N(char, RSTRING_LEN(string) * 2 + 1); if( rb_obj_is_kind_of(self, rb_cPGconn) ) { size = PQescapeStringConn(pg_get_pgconn(self), escaped, RSTRING_PTR(string), RSTRING_LEN(string), &error); if(error) { xfree(escaped); rb_raise(rb_ePGerror, "%s", PQerrorMessage(pg_get_pgconn(self))); } } else { size = PQescapeString(escaped, RSTRING_PTR(string), RSTRING_LENINT(string)); } result = rb_str_new(escaped, size); xfree(escaped); OBJ_INFECT(result, string); PG_ENCODING_SET_NOCHECK(result, ENCODING_GET( rb_obj_is_kind_of(self, rb_cPGconn) ? self : string )); return result; }
Create a connection to the specified server.
- host
-
server hostname
- hostaddr
-
server address (avoids hostname lookup, overrides
host
) - port
-
server port number
- dbname
-
connecting database name
- user
-
login user name
- password
-
login password
- connect_timeout
-
maximum time to wait for connection to succeed
- options
-
backend options
- tty
-
(ignored in newer versions of PostgreSQL)
- sslmode
-
(disable|allow|prefer|require)
- krbsrvname
-
kerberos service name
- gsslib
-
GSS library to use for GSSAPI authentication
- service
-
service name to use for additional parameters
Examples:
# Connect using all defaults PG::Connection.new # As a Hash PG::Connection.new( :dbname => 'test', :port => 5432 ) # As a String PG::Connection.new( "dbname=test port=5432" ) # As an Array PG::Connection.new( nil, 5432, nil, nil, 'test', nil, nil )
If the Ruby default internal encoding is set (i.e.,
Encoding.default_internal != nil), the connection will have its
client_encoding
set accordingly.
Raises a PG::Error if the connection fails.
static VALUE pgconn_init(int argc, VALUE *argv, VALUE self) { t_pg_connection *this; VALUE conninfo; VALUE error; this = pg_get_connection( self ); conninfo = rb_funcall2( rb_cPGconn, rb_intern("parse_connect_args"), argc, argv ); this->pgconn = gvl_PQconnectdb(StringValueCStr(conninfo)); if(this->pgconn == NULL) rb_raise(rb_ePGerror, "PQconnectdb() unable to allocate structure"); if (PQstatus(this->pgconn) == CONNECTION_BAD) { error = rb_exc_new2(rb_eConnectionBad, PQerrorMessage(this->pgconn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } #ifdef M17N_SUPPORTED pgconn_set_default_encoding( self ); #endif if (rb_block_given_p()) { return rb_ensure(rb_yield, self, pgconn_finish, self); } return self; }
Parse the connection args
into a connection-parameter string.
See ::new for valid arguments.
# File lib/pg/connection.rb, line 35 def self::parse_connect_args( *args ) return '' if args.empty? hash_arg = args.last.is_a?( Hash ) ? args.pop : {} option_string = '' options = {} # Parameter 'fallback_application_name' was introduced in PostgreSQL 9.0 # together with PQescapeLiteral(). if PG::Connection.instance_methods.find {|m| m.to_sym == :escape_literal } options[:fallback_application_name] = $0.sub( /^(.{30}).{4,}(.{30})$/ ){ $1+"..."+$2 } end if args.length == 1 case args.first when URI, URI.regexp uri = URI(args.first) options.merge!( Hash[URI.decode_www_form( uri.query )] ) if uri.query when /=/ # Option string style option_string = args.first.to_s else # Positional parameters options[CONNECT_ARGUMENT_ORDER.first.to_sym] = args.first end else max = CONNECT_ARGUMENT_ORDER.length raise ArgumentError, "Extra positional parameter %d: %p" % [ max + 1, args[max] ] if args.length > max CONNECT_ARGUMENT_ORDER.zip( args ) do |(k,v)| options[ k.to_sym ] = v if v end end options.merge!( hash_arg ) if uri uri.host = nil if options[:host] uri.port = nil if options[:port] uri.user = nil if options[:user] uri.password = nil if options[:password] uri.path = '' if options[:dbname] uri.query = URI.encode_www_form( options ) return uri.to_s.sub( /^#{uri.scheme}:(?!\/\/)/, "#{uri.scheme}://" ) else option_string += ' ' unless option_string.empty? && options.empty? return option_string + options.map { |k,v| "#{k}=#{quote_connstr(v)}" }.join( ' ' ) end end
Check server status.
Returns one of:
- PQPING_OK
-
server is accepting connections
- PQPING_REJECT
-
server is alive but rejecting connections
- PQPING_NO_RESPONSE
-
could not establish connection
- PQPING_NO_ATTEMPT
-
connection not attempted (bad params)
static VALUE pgconn_s_ping( int argc, VALUE *argv, VALUE klass ) { PGPing ping; VALUE conninfo; conninfo = rb_funcall2( klass, rb_intern("parse_connect_args"), argc, argv ); ping = PQping( StringValueCStr(conninfo) ); return INT2FIX((int)ping); }
Quote the given value
for use in a connection-parameter
string.
# File lib/pg/connection.rb, line 28 def self::quote_connstr( value ) return "'" + value.to_s.gsub( /[\']/ ) {|m| '\' + m } + "'" end
Returns a string that is safe for inclusion in a SQL query as an identifier. Note: this is not a quote function for values, but for identifiers.
For example, in a typical SQL query: SELECT FOO FROM MYTABLE
The identifier FOO
is folded to lower case, so it actually
means foo
. If you really want to access the case-sensitive
field name FOO
, use this function like
PG::Connection.quote_ident('FOO')
, which will return
"FOO"
(with double-quotes). PostgreSQL will see the
double-quotes, and it will not fold to lower case.
Similarly, this function also protects against special characters, and other things that might allow SQL injection if the identifier comes from an untrusted source.
If the parameter is an Array, then all it's values are separately quoted and then joined by a “.” character. This can be used for identifiers in the form “schema”.“table”.“column” .
This method is functional identical to the encoder PG::TextEncoder::Identifier .
static VALUE pgconn_s_quote_ident(VALUE self, VALUE in_str) { VALUE ret; pg_text_enc_identifier(NULL, in_str, NULL, &ret); OBJ_INFECT(ret, in_str); PG_ENCODING_SET_NOCHECK(ret, ENCODING_GET( rb_obj_is_kind_of(self, rb_cPGconn) ? self : in_str )); return ret; }
Converts an escaped string representation of binary data into binary data —
the reverse of escape_bytea. This is
needed when retrieving bytea
data in text format, but not when
retrieving it in binary format.
static VALUE pgconn_s_unescape_bytea(VALUE self, VALUE str) { unsigned char *from, *to; size_t to_len; VALUE ret; UNUSED( self ); Check_Type(str, T_STRING); from = (unsigned char*)StringValueCStr(str); to = PQunescapeBytea(from, &to_len); ret = rb_str_new((char*)to, to_len); OBJ_INFECT(ret, str); PQfreemem(to); return ret; }
Public Instance Methods
This function has the same behavior as exec, but is implemented using the asynchronous command processing API of libpq.
static VALUE pgconn_async_exec(int argc, VALUE *argv, VALUE self) { VALUE rb_pgresult = Qnil; /* remove any remaining results from the queue */ pgconn_block( 0, NULL, self ); /* wait for input (without blocking) before reading the last result */ pgconn_get_last_result( self ); pgconn_send_query( argc, argv, self ); pgconn_block( 0, NULL, self ); rb_pgresult = pgconn_get_last_result( self ); if ( rb_block_given_p() ) { return rb_ensure( rb_yield, rb_pgresult, pg_result_clear, rb_pgresult ); } return rb_pgresult; }
Returns the process ID of the backend server process for this connection. Note that this is a PID on database server host.
static VALUE pgconn_backend_pid(VALUE self) { return INT2NUM(PQbackendPID(pg_get_pgconn(self))); }
Blocks until the server is no longer busy, or until the optional timeout is reached, whichever comes first. timeout is measured in seconds and can be fractional.
Returns false
if timeout is reached,
true
otherwise.
If true
is returned, conn.is_busy
will return
false
and conn.get_result
will not block.
static VALUE pgconn_block( int argc, VALUE *argv, VALUE self ) { PGconn *conn = pg_get_pgconn( self ); /* If WIN32 and Ruby 1.9 do not use rb_thread_select() which sometimes hangs * and does not wait (nor sleep) any time even if timeout is given. * Instead use the Winsock events and rb_w32_wait_events(). */ struct timeval timeout; struct timeval *ptimeout = NULL; VALUE timeout_in; double timeout_sec; void *ret; if ( rb_scan_args(argc, argv, "01", &timeout_in) == 1 ) { timeout_sec = NUM2DBL( timeout_in ); timeout.tv_sec = (time_t)timeout_sec; timeout.tv_usec = (suseconds_t)((timeout_sec - (long)timeout_sec) * 1e6); ptimeout = &timeout; } ret = wait_socket_readable( conn, ptimeout, get_result_readable); if( !ret ) return Qfalse; return Qtrue; }
Requests cancellation of the command currently being processed. (Only implemented in PostgreSQL >= 8.0)
Returns nil
on success, or a string containing the error
message if a failure occurs.
static VALUE pgconn_cancel(VALUE self) { #ifdef HAVE_PQGETCANCEL char errbuf[256]; PGcancel *cancel; VALUE retval; int ret; cancel = PQgetCancel(pg_get_pgconn(self)); if(cancel == NULL) rb_raise(rb_ePGerror,"Invalid connection!"); ret = gvl_PQcancel(cancel, errbuf, 256); if(ret == 1) retval = Qnil; else retval = rb_str_new2(errbuf); PQfreeCancel(cancel); return retval; #else rb_notimplement(); #endif }
Returns an array of Hashes with connection defaults. See ::conndefaults for details.
# File lib/pg/connection.rb, line 193 def conndefaults return self.class.conndefaults end
Returns a Hash with connection defaults. See ::conndefaults_hash for details.
# File lib/pg/connection.rb, line 209 def conndefaults_hash return self.class.conndefaults_hash end
Returns one of:
- PGRES_POLLING_READING
-
wait until the socket is ready to read
- PGRES_POLLING_WRITING
-
wait until the socket is ready to write
- PGRES_POLLING_FAILED
-
the asynchronous connection has failed
- PGRES_POLLING_OK
-
the asynchronous connection is ready
Example:
conn = PG::Connection.connect_start("dbname=mydatabase") socket = conn.socket_io status = conn.connect_poll while(status != PG::PGRES_POLLING_OK) do # do some work while waiting for the connection to complete if(status == PG::PGRES_POLLING_READING) if(not select([socket], [], [], 10.0)) raise "Asynchronous connection timed out!" end elsif(status == PG::PGRES_POLLING_WRITING) if(not select([], [socket], [], 10.0)) raise "Asynchronous connection timed out!" end end status = conn.connect_poll end # now conn.status == CONNECTION_OK, and connection # is ready.
static VALUE pgconn_connect_poll(VALUE self) { PostgresPollingStatusType status; status = gvl_PQconnectPoll(pg_get_pgconn(self)); return INT2FIX((int)status); }
Returns true
if the authentication method required a password,
but none was available. false
otherwise.
static VALUE pgconn_connection_needs_password(VALUE self) { return PQconnectionNeedsPassword(pg_get_pgconn(self)) ? Qtrue : Qfalse; }
Returns true
if the authentication method used a
caller-supplied password, false
otherwise.
static VALUE pgconn_connection_used_password(VALUE self) { return PQconnectionUsedPassword(pg_get_pgconn(self)) ? Qtrue : Qfalse; }
Returns the connection options used by a live connection.
static VALUE pgconn_conninfo( VALUE self ) { PGconn *conn = pg_get_pgconn(self); PQconninfoOption *options = PQconninfo( conn ); VALUE array = pgconn_make_conninfo_array( options ); PQconninfoFree(options); return array; }
Return the Postgres connection info structure as a Hash keyed by option keyword (as a Symbol).
See also conninfo
# File lib/pg/connection.rb, line 220 def conninfo_hash return self.conninfo.each_with_object({}) do |info, hash| hash[ info[:keyword].to_sym ] = info[:val] end end
If input is available from the server, consume it. After calling
consume_input
, you can check is_busy
or
notifies to see if the state has changed.
static VALUE pgconn_consume_input(self) VALUE self; { VALUE error; PGconn *conn = pg_get_pgconn(self); /* returns 0 on error */ if(PQconsumeInput(conn) == 0) { error = rb_exc_new2(rb_eConnectionBad, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
Execute a copy process for transfering data to or from the server.
This issues the SQL COPY command via exec. The response to this (if there is no error in the command) is a PG::Result object that is passed to the block, bearing a status code of PGRES_COPY_OUT or PGRES_COPY_IN (depending on the specified copy direction). The application should then use put_copy_data or get_copy_data to receive or transmit data rows and should return from the block when finished.
copy_data returns another PG::Result object when the data transfer is complete. An exception is raised if some problem was encountered, so it isn't required to make use of any of them. At this point further SQL commands can be issued via exec. (It is not possible to execute other SQL commands using the same connection while the COPY operation is in progress.)
This method ensures, that the copy process is properly terminated in case of client side or server side failures. Therefore, in case of blocking mode of operation, copy_data is preferred to raw calls of put_copy_data, get_copy_data and put_copy_end.
Example with CSV input format:
conn.exec "create table my_table (a text,b text,c text,d text,e text)" conn.copy_data "COPY my_table FROM STDIN CSV" do conn.put_copy_data "some,csv,data,to,copy\n" conn.put_copy_data "more,csv,data,to,copy\n" end
This creates my_table
and inserts two rows.
Example with CSV output format:
conn.copy_data "COPY my_table TO STDOUT CSV" do while row=conn.get_copy_data p row end end
This prints all rows of my_table
to stdout:
"some,csv,data,to,copy\n" "more,csv,data,to,copy\n"
# File lib/pg/connection.rb, line 129 def copy_data( sql, coder=nil ) res = exec( sql ) case res.result_status when PGRES_COPY_IN begin if coder old_coder = self.encoder_for_put_copy_data self.encoder_for_put_copy_data = coder end yield res rescue Exception => err errmsg = "%s while copy data: %s" % [ err.class.name, err.message ] put_copy_end( errmsg ) get_result raise else put_copy_end get_last_result ensure self.encoder_for_put_copy_data = old_coder if coder end when PGRES_COPY_OUT begin if coder old_coder = self.decoder_for_get_copy_data self.decoder_for_get_copy_data = coder end yield res rescue Exception => err cancel while get_copy_data end while get_result end raise else res = get_last_result if res.result_status != PGRES_COMMAND_OK while get_copy_data end while get_result end raise PG::NotAllCopyDataRetrieved, "Not all COPY data retrieved" end res ensure self.decoder_for_get_copy_data = old_coder if coder end else raise ArgumentError, "SQL command is no COPY statement: #{sql}" end end
Returns the connected database name.
static VALUE pgconn_db(VALUE self) { char *db = PQdb(pg_get_pgconn(self)); if (!db) return Qnil; return rb_tainted_str_new2(db); }
Returns the default coder object that is currently set for type casting of received data by get_copy_data .
Returns either:
-
a kind of PG::Coder
-
nil
- type encoding is disabled, returned data will be a String.
static VALUE pgconn_decoder_for_get_copy_data_get(VALUE self) { t_pg_connection *this = pg_get_connection( self ); return this->decoder_for_get_copy_data; }
Set the default coder that is used for type casting of received data by get_copy_data .
decoder
can be:
-
a kind of PG::Coder
-
nil
- disable type decoding, returned data will be a String.
static VALUE pgconn_decoder_for_get_copy_data_set(VALUE self, VALUE typemap) { t_pg_connection *this = pg_get_connection( self ); if( typemap != Qnil ){ if ( !rb_obj_is_kind_of(typemap, rb_cPG_Coder) ) { rb_raise( rb_eTypeError, "wrong argument type %s (expected kind of PG::Coder)", rb_obj_classname( typemap ) ); } Check_Type(typemap, T_DATA); } this->decoder_for_get_copy_data = typemap; return typemap; }
Retrieve information about the portal portal_name.
static VALUE pgconn_describe_portal(self, stmt_name) VALUE self, stmt_name; { PGresult *result; VALUE rb_pgresult; PGconn *conn = pg_get_pgconn(self); char *stmt; if(stmt_name == Qnil) { stmt = NULL; } else { Check_Type(stmt_name, T_STRING); stmt = StringValueCStr(stmt_name); } result = gvl_PQdescribePortal(conn, stmt); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); return rb_pgresult; }
Retrieve information about the prepared statement statement_name.
static VALUE pgconn_describe_prepared(VALUE self, VALUE stmt_name) { PGresult *result; VALUE rb_pgresult; PGconn *conn = pg_get_pgconn(self); char *stmt; if(stmt_name == Qnil) { stmt = NULL; } else { Check_Type(stmt_name, T_STRING); stmt = StringValueCStr(stmt_name); } result = gvl_PQdescribePrepared(conn, stmt); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); return rb_pgresult; }
Returns the default coder object that is currently set for type casting of parameters to put_copy_data .
Returns either:
-
a kind of PG::Coder
-
nil
- type encoding is disabled, returned data will be a String.
static VALUE pgconn_encoder_for_put_copy_data_get(VALUE self) { t_pg_connection *this = pg_get_connection( self ); return this->encoder_for_put_copy_data; }
Set the default coder that is used for type casting of parameters to put_copy_data .
encoder
can be:
-
a kind of PG::Coder
-
nil
- disable type encoding, data must be a String.
static VALUE pgconn_encoder_for_put_copy_data_set(VALUE self, VALUE typemap) { t_pg_connection *this = pg_get_connection( self ); if( typemap != Qnil ){ if ( !rb_obj_is_kind_of(typemap, rb_cPG_Coder) ) { rb_raise( rb_eTypeError, "wrong argument type %s (expected kind of PG::Coder)", rb_obj_classname( typemap ) ); } Check_Type(typemap, T_DATA); } this->encoder_for_put_copy_data = typemap; return typemap; }
Returns the error message about connection.
static VALUE pgconn_error_message(VALUE self) { char *error = PQerrorMessage(pg_get_pgconn(self)); if (!error) return Qnil; return rb_tainted_str_new2(error); }
Connection instance method for versions of 8.1 and higher of libpq uses PQescapeByteaConn, which is safer. Avoid calling as a class method, the class method uses the deprecated PQescapeBytea() API function.
Use the instance method version of this function, it is safer than the class method.
Escapes binary data for use within an SQL command with the type
bytea
.
Certain byte values must be escaped (but all byte values may be escaped)
when used as part of a bytea
literal in an SQL statement. In
general, to escape a byte, it is converted into the three digit octal
number equal to the octet value, and preceded by two backslashes. The
single quote (') and backslash () characters have special alternative
escape sequences. escape_bytea performs this
operation, escaping only the minimally required bytes.
Consider using #exec_params, which avoids the need for passing values inside of SQL commands.
static VALUE pgconn_s_escape_bytea(VALUE self, VALUE str) { unsigned char *from, *to; size_t from_len, to_len; VALUE ret; Check_Type(str, T_STRING); from = (unsigned char*)RSTRING_PTR(str); from_len = RSTRING_LEN(str); if ( rb_obj_is_kind_of(self, rb_cPGconn) ) { to = PQescapeByteaConn(pg_get_pgconn(self), from, from_len, &to_len); } else { to = PQescapeBytea( from, from_len, &to_len); } ret = rb_str_new((char*)to, to_len - 1); OBJ_INFECT(ret, str); PQfreemem(to); return ret; }
Escape an arbitrary String str
as an identifier.
This method does the same as quote_ident, but uses libpq to process the string.
static VALUE pgconn_escape_identifier(VALUE self, VALUE string) { PGconn *conn = pg_get_pgconn(self); char *escaped = NULL; VALUE error; VALUE result = Qnil; Check_Type(string, T_STRING); escaped = PQescapeIdentifier(conn, RSTRING_PTR(string), RSTRING_LEN(string)); if (escaped == NULL) { error = rb_exc_new2(rb_ePGerror, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); return Qnil; } result = rb_str_new2(escaped); PQfreemem(escaped); OBJ_INFECT(result, string); PG_ENCODING_SET_NOCHECK(result, ENCODING_GET(self)); return result; }
Escape an arbitrary String str
as a literal.
static VALUE pgconn_escape_literal(VALUE self, VALUE string) { PGconn *conn = pg_get_pgconn(self); char *escaped = NULL; VALUE error; VALUE result = Qnil; Check_Type(string, T_STRING); escaped = PQescapeLiteral(conn, RSTRING_PTR(string), RSTRING_LEN(string)); if (escaped == NULL) { error = rb_exc_new2(rb_ePGerror, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); return Qnil; } result = rb_str_new2(escaped); PQfreemem(escaped); OBJ_INFECT(result, string); PG_ENCODING_SET_NOCHECK(result, ENCODING_GET(self)); return result; }
Connection instance method for versions of 8.1 and higher of libpq uses PQescapeStringConn, which is safer. Avoid calling as a class method, the class method uses the deprecated PQescapeString() API function.
Returns a SQL-safe version of the String str. This is the preferred way to make strings safe for inclusion in SQL queries.
Consider using #exec_params, which avoids the need for passing values inside of SQL commands.
Encoding of escaped string will be equal to client encoding of connection.
static VALUE pgconn_s_escape(VALUE self, VALUE string) { char *escaped; size_t size; int error; VALUE result; Check_Type(string, T_STRING); escaped = ALLOC_N(char, RSTRING_LEN(string) * 2 + 1); if( rb_obj_is_kind_of(self, rb_cPGconn) ) { size = PQescapeStringConn(pg_get_pgconn(self), escaped, RSTRING_PTR(string), RSTRING_LEN(string), &error); if(error) { xfree(escaped); rb_raise(rb_ePGerror, "%s", PQerrorMessage(pg_get_pgconn(self))); } } else { size = PQescapeString(escaped, RSTRING_PTR(string), RSTRING_LENINT(string)); } result = rb_str_new(escaped, size); xfree(escaped); OBJ_INFECT(result, string); PG_ENCODING_SET_NOCHECK(result, ENCODING_GET( rb_obj_is_kind_of(self, rb_cPGconn) ? self : string )); return result; }
Sends SQL query request specified by sql to PostgreSQL. Returns a PG::Result instance on success. On failure, it raises a PG::Error.
For backward compatibility, if you pass more than one parameter to this method, it will call exec_params for you. New code should explicitly use exec_params if argument placeholders are used.
If the optional code block is given, it will be passed result as
an argument, and the PG::Result object will
automatically be cleared when the block terminates. In this instance,
conn.exec
returns the value of the block.
exec is implemented on the synchronous command processing API of libpq, whereas async_exec is implemented on the asynchronous API. exec is somewhat faster that async_exec, but blocks any signals to be processed until the query is finished. This is most notably visible by a delayed reaction to Control+C. Both methods ensure that other threads can process while waiting for the server to complete the request.
static VALUE pgconn_exec(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn(self); PGresult *result = NULL; VALUE rb_pgresult; /* If called with no parameters, use PQexec */ if ( argc == 1 ) { Check_Type(argv[0], T_STRING); result = gvl_PQexec(conn, StringValueCStr(argv[0])); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); if (rb_block_given_p()) { return rb_ensure(rb_yield, rb_pgresult, pg_result_clear, rb_pgresult); } return rb_pgresult; } /* Otherwise, just call #exec_params instead for backward-compatibility */ else { return pgconn_exec_params( argc, argv, self ); } }
Sends SQL query request specified by sql
to PostgreSQL using
placeholders for parameters.
Returns a PG::Result instance on success. On failure, it raises a PG::Error.
params
is an array of the bind parameters for the SQL query.
Each element of the params
array may be either:
a hash of the form: {:value => String (value of bind parameter) :type => Fixnum (oid of type of bind parameter) :format => Fixnum (0 for text, 1 for binary) } or, it may be a String. If it is a string, that is equivalent to the hash: { :value => <string value>, :type => 0, :format => 0 }
PostgreSQL bind parameters are represented as $1, $1, $2, etc., inside the
SQL query. The 0th element of the params
array is bound to $1,
the 1st element is bound to $2, etc. nil
is treated as
NULL
.
If the types are not specified, they will be inferred by PostgreSQL. Instead of specifying type oids, it's recommended to simply add explicit casts in the query to ensure that the right type is used.
For example: “SELECT $1::int”
The optional result_format
should be 0 for text results, 1 for
binary.
type_map can be a PG::TypeMap derivation (such as PG::BasicTypeMapForQueries). This will type cast the params form various Ruby types before transmission based on the encoders defined by the type map. When a type encoder is used the format and oid of a given bind parameter are retrieved from the encoder instead out of the hash form described above.
If the optional code block is given, it will be passed result as
an argument, and the PG::Result object will
automatically be cleared when the block terminates. In this instance,
conn.exec
returns the value of the block.
static VALUE pgconn_exec_params( int argc, VALUE *argv, VALUE self ) { PGconn *conn = pg_get_pgconn(self); PGresult *result = NULL; VALUE rb_pgresult; VALUE command, in_res_fmt; int nParams; int resultFormat; struct query_params_data paramsData; rb_scan_args(argc, argv, "13", &command, ¶msData.params, &in_res_fmt, ¶msData.typemap); paramsData.with_types = 1; /* * Handle the edge-case where the caller is coming from #exec, but passed an explict +nil+ * for the second parameter. */ if ( NIL_P(paramsData.params) ) { return pgconn_exec( 1, argv, self ); } pgconn_query_assign_typemap( self, ¶msData ); resultFormat = NIL_P(in_res_fmt) ? 0 : NUM2INT(in_res_fmt); nParams = alloc_query_params( ¶msData ); result = gvl_PQexecParams(conn, StringValueCStr(command), nParams, paramsData.types, (const char * const *)paramsData.values, paramsData.lengths, paramsData.formats, resultFormat); free_query_params( ¶msData ); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); if (rb_block_given_p()) { return rb_ensure(rb_yield, rb_pgresult, pg_result_clear, rb_pgresult); } return rb_pgresult; }
Execute prepared named statement specified by statement_name. Returns a PG::Result instance on success. On failure, it raises a PG::Error.
params
is an array of the optional bind parameters for the SQL
query. Each element of the params
array may be either:
a hash of the form: {:value => String (value of bind parameter) :format => Fixnum (0 for text, 1 for binary) } or, it may be a String. If it is a string, that is equivalent to the hash: { :value => <string value>, :format => 0 }
PostgreSQL bind parameters are represented as $1, $1, $2, etc., inside the
SQL query. The 0th element of the params
array is bound to $1,
the 1st element is bound to $2, etc. nil
is treated as
NULL
.
The optional result_format
should be 0 for text results, 1 for
binary.
type_map can be a PG::TypeMap derivation (such as PG::BasicTypeMapForQueries). This will type cast the params form various Ruby types before transmission based on the encoders defined by the type map. When a type encoder is used the format and oid of a given bind parameter are retrieved from the encoder instead out of the hash form described above.
If the optional code block is given, it will be passed result as
an argument, and the PG::Result object will
automatically be cleared when the block terminates. In this instance,
conn.exec_prepared
returns the value of the block.
static VALUE pgconn_exec_prepared(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn(self); PGresult *result = NULL; VALUE rb_pgresult; VALUE name, in_res_fmt; int nParams; int resultFormat; struct query_params_data paramsData; rb_scan_args(argc, argv, "13", &name, ¶msData.params, &in_res_fmt, ¶msData.typemap); paramsData.with_types = 0; Check_Type(name, T_STRING); if(NIL_P(paramsData.params)) { paramsData.params = rb_ary_new2(0); } pgconn_query_assign_typemap( self, ¶msData ); resultFormat = NIL_P(in_res_fmt) ? 0 : NUM2INT(in_res_fmt); nParams = alloc_query_params( ¶msData ); result = gvl_PQexecPrepared(conn, StringValueCStr(name), nParams, (const char * const *)paramsData.values, paramsData.lengths, paramsData.formats, resultFormat); free_query_params( ¶msData ); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); if (rb_block_given_p()) { return rb_ensure(rb_yield, rb_pgresult, pg_result_clear, rb_pgresult); } return rb_pgresult; }
Return the server_encoding
of the connected database as a Ruby
Encoding object. The SQL_ASCII
encoding is mapped to to
ASCII_8BIT
.
static VALUE pgconn_external_encoding(VALUE self) { t_pg_connection *this = pg_get_connection_safe( self ); rb_encoding *enc = NULL; const char *pg_encname = NULL; /* Use cached value if found */ if ( RTEST(this->external_encoding) ) return this->external_encoding; pg_encname = PQparameterStatus( this->pgconn, "server_encoding" ); enc = pg_get_pg_encname_as_rb_encoding( pg_encname ); this->external_encoding = rb_enc_from_encoding( enc ); return this->external_encoding; }
Closes the backend connection.
static VALUE pgconn_finish( VALUE self ) { t_pg_connection *this = pg_get_connection_safe( self ); pgconn_close_socket_io( self ); PQfinish( this->pgconn ); this->pgconn = NULL; return Qnil; }
Returns true
if the backend connection has been closed.
static VALUE pgconn_finished_p( VALUE self ) { t_pg_connection *this = pg_get_connection( self ); if ( this->pgconn ) return Qfalse; return Qtrue; }
Attempts to flush any queued output data to the server. Returns
true
if data is successfully flushed, false
if
not (can only return false
if connection is nonblocking.
Raises PG::Error if some other failure occurred.
static VALUE pgconn_flush(self) VALUE self; { PGconn *conn = pg_get_pgconn(self); int ret; VALUE error; ret = PQflush(conn); if(ret == -1) { error = rb_exc_new2(rb_ePGerror, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return (ret) ? Qfalse : Qtrue; }
Returns the client encoding as a String.
static VALUE pgconn_get_client_encoding(VALUE self) { char *encoding = (char *)pg_encoding_to_char(PQclientEncoding(pg_get_pgconn(self))); return rb_tainted_str_new2(encoding); }
Return a string containing one row of data, nil
if the copy is
done, or false
if the call would block (only possible if
async is true).
decoder can be a PG::Coder derivation (typically PG::TextDecoder::CopyRow). This decodes the received data fields as Array of Strings. Optionally the decoder can type cast the fields to various Ruby types in one step, if PG::CopyCoder#type_map is set accordingly.
See also copy_data.
static VALUE pgconn_get_copy_data(int argc, VALUE *argv, VALUE self ) { VALUE async_in; VALUE error; VALUE result; int ret; char *buffer; VALUE decoder; t_pg_coder *p_coder = NULL; t_pg_connection *this = pg_get_connection_safe( self ); rb_scan_args(argc, argv, "02", &async_in, &decoder); if( NIL_P(decoder) ){ if( !NIL_P(this->decoder_for_get_copy_data) ){ p_coder = DATA_PTR( this->decoder_for_get_copy_data ); } } else if( rb_obj_is_kind_of(decoder, rb_cPG_Coder) ) { Data_Get_Struct( decoder, t_pg_coder, p_coder ); } else { rb_raise( rb_eTypeError, "wrong decoder type %s (expected some kind of PG::Coder)", rb_obj_classname( decoder ) ); } ret = gvl_PQgetCopyData(this->pgconn, &buffer, RTEST(async_in)); if(ret == -2) { /* error */ error = rb_exc_new2(rb_ePGerror, PQerrorMessage(this->pgconn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } if(ret == -1) { /* No data left */ return Qnil; } if(ret == 0) { /* would block */ return Qfalse; } if( p_coder ){ t_pg_coder_dec_func dec_func = pg_coder_dec_func( p_coder, p_coder->format ); result = dec_func( p_coder, buffer, ret, 0, 0, ENCODING_GET(self) ); } else { result = rb_tainted_str_new(buffer, ret); } PQfreemem(buffer); return result; }
This function retrieves all available results on the current connection
(from previously issued asynchronous commands like +send_query()+) and
returns the last non-NULL result, or nil
if no results are
available.
This function is similar to get_result except that it is designed to get one and only one result.
static VALUE pgconn_get_last_result(VALUE self) { PGconn *conn = pg_get_pgconn(self); VALUE rb_pgresult = Qnil; PGresult *cur, *prev; cur = prev = NULL; while ((cur = gvl_PQgetResult(conn)) != NULL) { int status; if (prev) PQclear(prev); prev = cur; status = PQresultStatus(cur); if (status == PGRES_COPY_OUT || status == PGRES_COPY_IN) break; } if (prev) { rb_pgresult = pg_new_result( prev, self ); pg_result_check(rb_pgresult); } return rb_pgresult; }
Blocks waiting for the next result from a call to send_query (or another
asynchronous command), and returns it. Returns nil
if no more
results are available.
Note: call this function repeatedly until it returns nil
, or
else you will not be able to issue further commands.
If the optional code block is given, it will be passed result as
an argument, and the PG::Result object will
automatically be cleared when the block terminates. In this instance,
conn.exec
returns the value of the block.
static VALUE pgconn_get_result(VALUE self) { PGconn *conn = pg_get_pgconn(self); PGresult *result; VALUE rb_pgresult; result = gvl_PQgetResult(conn); if(result == NULL) return Qnil; rb_pgresult = pg_new_result(result, self); if (rb_block_given_p()) { return rb_ensure(rb_yield, rb_pgresult, pg_result_clear, rb_pgresult); } return rb_pgresult; }
Returns the connected server name.
static VALUE pgconn_host(VALUE self) { char *host = PQhost(pg_get_pgconn(self)); if (!host) return Qnil; return rb_tainted_str_new2(host); }
defined in Ruby 1.9 or later.
Returns:
-
an Encoding - client_encoding of the connection as a Ruby Encoding object.
-
nil - the client_encoding is 'SQL_ASCII'
static VALUE pgconn_internal_encoding(VALUE self) { PGconn *conn = pg_get_pgconn( self ); rb_encoding *enc = pg_conn_enc_get( conn ); if ( enc ) { return rb_enc_from_encoding( enc ); } else { return Qnil; } }
A wrapper of set_client_encoding. defined in Ruby 1.9 or later.
value
can be one of:
-
an Encoding
-
a String - a name of Encoding
-
nil
- sets the client_encoding to SQL_ASCII.
static VALUE pgconn_internal_encoding_set(VALUE self, VALUE enc) { VALUE enc_inspect; if (NIL_P(enc)) { pgconn_set_client_encoding( self, rb_usascii_str_new_cstr("SQL_ASCII") ); return enc; } else if ( TYPE(enc) == T_STRING && strcasecmp("JOHAB", StringValueCStr(enc)) == 0 ) { pgconn_set_client_encoding(self, rb_usascii_str_new_cstr("JOHAB")); return enc; } else { rb_encoding *rbenc = rb_to_encoding( enc ); const char *name = pg_get_rb_encoding_as_pg_encoding( rbenc ); if ( PQsetClientEncoding(pg_get_pgconn( self ), name) == -1 ) { VALUE server_encoding = pgconn_external_encoding( self ); rb_raise( rb_eEncCompatError, "incompatible character encodings: %s and %s", rb_enc_name(rb_to_encoding(server_encoding)), name ); } pgconn_set_internal_encoding_index( self ); return enc; } enc_inspect = rb_inspect(enc); rb_raise( rb_ePGerror, "unknown encoding: %s", StringValueCStr(enc_inspect) ); return Qnil; }
Returns true
if a command is busy, that is, if PQgetResult
would block. Otherwise returns false
.
static VALUE pgconn_is_busy(self) VALUE self; { return gvl_PQisBusy(pg_get_pgconn(self)) ? Qtrue : Qfalse; }
Returns true
if a command is busy, that is, if PQgetResult
would block. Otherwise returns false
.
static VALUE pgconn_isnonblocking(self) VALUE self; { return PQisnonblocking(pg_get_pgconn(self)) ? Qtrue : Qfalse; }
Closes the postgres large object of lo_desc.
static VALUE pgconn_loclose(VALUE self, VALUE in_lo_desc) { PGconn *conn = pg_get_pgconn(self); int lo_desc = NUM2INT(in_lo_desc); if(lo_close(conn,lo_desc) < 0) rb_raise(rb_ePGerror,"lo_close failed"); return Qnil; }
Creates a large object with mode mode. Returns a large object Oid. On failure, it raises PG::Error.
static VALUE pgconn_locreat(int argc, VALUE *argv, VALUE self) { Oid lo_oid; int mode; VALUE nmode; PGconn *conn = pg_get_pgconn(self); if (rb_scan_args(argc, argv, "01", &nmode) == 0) mode = INV_READ; else mode = NUM2INT(nmode); lo_oid = lo_creat(conn, mode); if (lo_oid == 0) rb_raise(rb_ePGerror, "lo_creat failed"); return UINT2NUM(lo_oid); }
Creates a large object with oid oid. Returns the large object Oid. On failure, it raises PG::Error.
static VALUE pgconn_locreate(VALUE self, VALUE in_lo_oid) { Oid ret, lo_oid; PGconn *conn = pg_get_pgconn(self); lo_oid = NUM2UINT(in_lo_oid); ret = lo_create(conn, lo_oid); if (ret == InvalidOid) rb_raise(rb_ePGerror, "lo_create failed"); return UINT2NUM(ret); }
Saves a large object of oid to a file.
static VALUE pgconn_loexport(VALUE self, VALUE lo_oid, VALUE filename) { PGconn *conn = pg_get_pgconn(self); Oid oid; Check_Type(filename, T_STRING); oid = NUM2UINT(lo_oid); if (lo_export(conn, oid, StringValueCStr(filename)) < 0) { rb_raise(rb_ePGerror, "%s", PQerrorMessage(conn)); } return Qnil; }
Import a file to a large object. Returns a large object Oid.
On failure, it raises a PG::Error.
static VALUE pgconn_loimport(VALUE self, VALUE filename) { Oid lo_oid; PGconn *conn = pg_get_pgconn(self); Check_Type(filename, T_STRING); lo_oid = lo_import(conn, StringValueCStr(filename)); if (lo_oid == 0) { rb_raise(rb_ePGerror, "%s", PQerrorMessage(conn)); } return UINT2NUM(lo_oid); }
Move the large object pointer lo_desc to offset offset.
Valid values for whence are SEEK_SET
,
SEEK_CUR
, and SEEK_END
. (Or 0, 1, or 2.)
static VALUE pgconn_lolseek(VALUE self, VALUE in_lo_desc, VALUE offset, VALUE whence) { PGconn *conn = pg_get_pgconn(self); int lo_desc = NUM2INT(in_lo_desc); int ret; if((ret = lo_lseek(conn, lo_desc, NUM2INT(offset), NUM2INT(whence))) < 0) { rb_raise(rb_ePGerror, "lo_lseek failed"); } return INT2FIX(ret); }
Open a large object of oid. Returns a large object descriptor
instance on success. The mode argument specifies the mode for the
opened large object,which is either INV_READ
, or
INV_WRITE
.
If mode is omitted, the default is INV_READ
.
static VALUE pgconn_loopen(int argc, VALUE *argv, VALUE self) { Oid lo_oid; int fd, mode; VALUE nmode, selfid; PGconn *conn = pg_get_pgconn(self); rb_scan_args(argc, argv, "11", &selfid, &nmode); lo_oid = NUM2UINT(selfid); if(NIL_P(nmode)) mode = INV_READ; else mode = NUM2INT(nmode); if((fd = lo_open(conn, lo_oid, mode)) < 0) { rb_raise(rb_ePGerror, "can't open large object: %s", PQerrorMessage(conn)); } return INT2FIX(fd); }
Attempts to read len bytes from large object lo_desc, returns resulting data.
static VALUE pgconn_loread(VALUE self, VALUE in_lo_desc, VALUE in_len) { int ret; PGconn *conn = pg_get_pgconn(self); int len = NUM2INT(in_len); int lo_desc = NUM2INT(in_lo_desc); VALUE str; char *buffer; buffer = ALLOC_N(char, len); if(buffer == NULL) rb_raise(rb_eNoMemError, "ALLOC failed!"); if (len < 0){ rb_raise(rb_ePGerror,"nagative length %d given", len); } if((ret = lo_read(conn, lo_desc, buffer, len)) < 0) rb_raise(rb_ePGerror, "lo_read failed"); if(ret == 0) { xfree(buffer); return Qnil; } str = rb_tainted_str_new(buffer, ret); xfree(buffer); return str; }
Returns the current position of the large object lo_desc.
static VALUE pgconn_lotell(VALUE self, VALUE in_lo_desc) { int position; PGconn *conn = pg_get_pgconn(self); int lo_desc = NUM2INT(in_lo_desc); if((position = lo_tell(conn, lo_desc)) < 0) rb_raise(rb_ePGerror,"lo_tell failed"); return INT2FIX(position); }
Truncates the large object lo_desc to size len.
static VALUE pgconn_lotruncate(VALUE self, VALUE in_lo_desc, VALUE in_len) { PGconn *conn = pg_get_pgconn(self); int lo_desc = NUM2INT(in_lo_desc); size_t len = NUM2INT(in_len); if(lo_truncate(conn,lo_desc,len) < 0) rb_raise(rb_ePGerror,"lo_truncate failed"); return Qnil; }
Unlinks (deletes) the postgres large object of oid.
static VALUE pgconn_lounlink(VALUE self, VALUE in_oid) { PGconn *conn = pg_get_pgconn(self); Oid oid = NUM2UINT(in_oid); if(lo_unlink(conn,oid) < 0) rb_raise(rb_ePGerror,"lo_unlink failed"); return Qnil; }
Writes the string buffer to the large object lo_desc. Returns the number of bytes written.
static VALUE pgconn_lowrite(VALUE self, VALUE in_lo_desc, VALUE buffer) { int n; PGconn *conn = pg_get_pgconn(self); int fd = NUM2INT(in_lo_desc); Check_Type(buffer, T_STRING); if( RSTRING_LEN(buffer) < 0) { rb_raise(rb_ePGerror, "write buffer zero string"); } if((n = lo_write(conn, fd, StringValuePtr(buffer), RSTRING_LEN(buffer))) < 0) { rb_raise(rb_ePGerror, "lo_write failed: %s", PQerrorMessage(conn)); } return INT2FIX(n); }
Constructs and empty PG::Result with status status. status may be one of:
-
PGRES_EMPTY_QUERY
-
PGRES_COMMAND_OK
-
PGRES_TUPLES_OK
-
PGRES_COPY_OUT
-
PGRES_COPY_IN
-
PGRES_BAD_RESPONSE
-
PGRES_NONFATAL_ERROR
-
PGRES_FATAL_ERROR
-
PGRES_COPY_BOTH
static VALUE pgconn_make_empty_pgresult(VALUE self, VALUE status) { PGresult *result; VALUE rb_pgresult; PGconn *conn = pg_get_pgconn(self); result = PQmakeEmptyPGresult(conn, NUM2INT(status)); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); return rb_pgresult; }
Returns a hash of the unprocessed notifications. If there is no unprocessed
notifier, it returns nil
.
static VALUE pgconn_notifies(VALUE self) { PGconn* conn = pg_get_pgconn(self); PGnotify *notification; VALUE hash; VALUE sym_relname, sym_be_pid, sym_extra; VALUE relname, be_pid, extra; sym_relname = ID2SYM(rb_intern("relname")); sym_be_pid = ID2SYM(rb_intern("be_pid")); sym_extra = ID2SYM(rb_intern("extra")); notification = gvl_PQnotifies(conn); if (notification == NULL) { return Qnil; } hash = rb_hash_new(); relname = rb_tainted_str_new2(notification->relname); be_pid = INT2NUM(notification->be_pid); extra = rb_tainted_str_new2(notification->extra); PG_ENCODING_SET_NOCHECK( relname, ENCODING_GET(self) ); PG_ENCODING_SET_NOCHECK( extra, ENCODING_GET(self) ); rb_hash_aset(hash, sym_relname, relname); rb_hash_aset(hash, sym_be_pid, be_pid); rb_hash_aset(hash, sym_extra, extra); PQfreemem(notification); return hash; }
Returns backend option string.
static VALUE pgconn_options(VALUE self) { char *options = PQoptions(pg_get_pgconn(self)); if (!options) return Qnil; return rb_tainted_str_new2(options); }
Returns the setting of parameter param_name, where param_name is one of
-
server_version
-
server_encoding
-
client_encoding
-
is_superuser
-
session_authorization
-
DateStyle
-
TimeZone
-
integer_datetimes
-
standard_conforming_strings
Returns nil if the value of the parameter is not known.
static VALUE pgconn_parameter_status(VALUE self, VALUE param_name) { const char *ret = PQparameterStatus(pg_get_pgconn(self), StringValueCStr(param_name)); if(ret == NULL) return Qnil; else return rb_tainted_str_new2(ret); }
Returns the authenticated user name.
static VALUE pgconn_pass(VALUE self) { char *user = PQpass(pg_get_pgconn(self)); if (!user) return Qnil; return rb_tainted_str_new2(user); }
Returns the connected server port number.
static VALUE pgconn_port(VALUE self) { char* port = PQport(pg_get_pgconn(self)); return INT2NUM(atol(port)); }
Prepares statement sql with name name to be executed later. Returns a PG::Result instance on success. On failure, it raises a PG::Error.
param_types
is an optional parameter to specify the Oids of
the types of the parameters.
If the types are not specified, they will be inferred by PostgreSQL. Instead of specifying type oids, it's recommended to simply add explicit casts in the query to ensure that the right type is used.
For example: “SELECT $1::int”
PostgreSQL bind parameters are represented as $1, $1, $2, etc., inside the SQL query.
static VALUE pgconn_prepare(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn(self); PGresult *result = NULL; VALUE rb_pgresult; VALUE name, command, in_paramtypes; VALUE param; int i = 0; int nParams = 0; Oid *paramTypes = NULL; rb_scan_args(argc, argv, "21", &name, &command, &in_paramtypes); Check_Type(name, T_STRING); Check_Type(command, T_STRING); if(! NIL_P(in_paramtypes)) { Check_Type(in_paramtypes, T_ARRAY); nParams = (int)RARRAY_LEN(in_paramtypes); paramTypes = ALLOC_N(Oid, nParams); for(i = 0; i < nParams; i++) { param = rb_ary_entry(in_paramtypes, i); if(param == Qnil) paramTypes[i] = 0; else paramTypes[i] = NUM2UINT(param); } } result = gvl_PQprepare(conn, StringValueCStr(name), StringValueCStr(command), nParams, paramTypes); xfree(paramTypes); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); return rb_pgresult; }
The 3.0 protocol will normally be used when communicating with PostgreSQL 7.4 or later servers; pre-7.4 servers support only protocol 2.0. (Protocol 1.0 is obsolete and not supported by libpq.)
static VALUE pgconn_protocol_version(VALUE self) { return INT2NUM(PQprotocolVersion(pg_get_pgconn(self))); }
Transmits buffer as copy data to the server. Returns true if the data was sent, false if it was not sent (false is only possible if the connection is in nonblocking mode, and this command would block).
encoder can be a PG::Coder derivation (typically PG::TextEncoder::CopyRow). This encodes the received data fields from an Array of Strings. Optionally the encoder can type cast the fields form various Ruby types in one step, if PG::CopyCoder#type_map is set accordingly.
Raises an exception if an error occurs.
See also copy_data.
static VALUE pgconn_put_copy_data(int argc, VALUE *argv, VALUE self) { int ret; int len; t_pg_connection *this = pg_get_connection_safe( self ); VALUE value; VALUE buffer = Qnil; VALUE encoder; VALUE intermediate; t_pg_coder *p_coder = NULL; rb_scan_args( argc, argv, "11", &value, &encoder ); if( NIL_P(encoder) ){ if( NIL_P(this->encoder_for_put_copy_data) ){ buffer = value; } else { p_coder = DATA_PTR( this->encoder_for_put_copy_data ); } } else if( rb_obj_is_kind_of(encoder, rb_cPG_Coder) ) { Data_Get_Struct( encoder, t_pg_coder, p_coder ); } else { rb_raise( rb_eTypeError, "wrong encoder type %s (expected some kind of PG::Coder)", rb_obj_classname( encoder ) ); } if( p_coder ){ t_pg_coder_enc_func enc_func; enc_func = pg_coder_enc_func( p_coder ); len = enc_func( p_coder, value, NULL, &intermediate ); if( len == -1 ){ /* The intermediate value is a String that can be used directly. */ buffer = intermediate; } else { buffer = rb_str_new(NULL, len); len = enc_func( p_coder, value, RSTRING_PTR(buffer), &intermediate); rb_str_set_len( buffer, len ); } } Check_Type(buffer, T_STRING); ret = gvl_PQputCopyData(this->pgconn, RSTRING_PTR(buffer), RSTRING_LENINT(buffer)); if(ret == -1) { VALUE error = rb_exc_new2(rb_ePGerror, PQerrorMessage(this->pgconn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } RB_GC_GUARD(intermediate); RB_GC_GUARD(buffer); return (ret) ? Qtrue : Qfalse; }
Sends end-of-data indication to the server.
error_message is an optional parameter, and if set, forces the COPY command to fail with the string error_message.
Returns true if the end-of-data was sent, false if it was not sent (false is only possible if the connection is in nonblocking mode, and this command would block).
static VALUE pgconn_put_copy_end(int argc, VALUE *argv, VALUE self) { VALUE str; VALUE error; int ret; char *error_message = NULL; PGconn *conn = pg_get_pgconn(self); if (rb_scan_args(argc, argv, "01", &str) == 0) error_message = NULL; else error_message = StringValueCStr(str); ret = gvl_PQputCopyEnd(conn, error_message); if(ret == -1) { error = rb_exc_new2(rb_ePGerror, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return (ret) ? Qtrue : Qfalse; }
Returns a string that is safe for inclusion in a SQL query as an identifier. Note: this is not a quote function for values, but for identifiers.
For example, in a typical SQL query: SELECT FOO FROM MYTABLE
The identifier FOO
is folded to lower case, so it actually
means foo
. If you really want to access the case-sensitive
field name FOO
, use this function like
PG::Connection.quote_ident('FOO')
, which will return
"FOO"
(with double-quotes). PostgreSQL will see the
double-quotes, and it will not fold to lower case.
Similarly, this function also protects against special characters, and other things that might allow SQL injection if the identifier comes from an untrusted source.
If the parameter is an Array, then all it's values are separately quoted and then joined by a “.” character. This can be used for identifiers in the form “schema”.“table”.“column” .
This method is functional identical to the encoder PG::TextEncoder::Identifier .
static VALUE pgconn_s_quote_ident(VALUE self, VALUE in_str) { VALUE ret; pg_text_enc_identifier(NULL, in_str, NULL, &ret); OBJ_INFECT(ret, in_str); PG_ENCODING_SET_NOCHECK(ret, ENCODING_GET( rb_obj_is_kind_of(self, rb_cPGconn) ? self : in_str )); return ret; }
Resets the backend connection. This method closes the backend connection and tries to re-connect.
static VALUE pgconn_reset( VALUE self ) { pgconn_close_socket_io( self ); gvl_PQreset( pg_get_pgconn(self) ); return self; }
Checks the status of a connection reset operation. See connect_start and connect_poll for usage information and return values.
static VALUE pgconn_reset_poll(VALUE self) { PostgresPollingStatusType status; status = gvl_PQresetPoll(pg_get_pgconn(self)); return INT2FIX((int)status); }
Initiate a connection reset in a nonblocking manner. This will close the current connection and attempt to reconnect using the same connection parameters. Use reset_poll to check the status of the connection reset.
static VALUE pgconn_reset_start(VALUE self) { pgconn_close_socket_io( self ); if(gvl_PQresetStart(pg_get_pgconn(self)) == 0) rb_raise(rb_eUnableToSend, "reset has failed"); return Qnil; }
Asynchronously send command to the server. Does not block. Use in
combination with conn.get_result
.
static VALUE pgconn_send_describe_portal(VALUE self, VALUE portal) { VALUE error; PGconn *conn = pg_get_pgconn(self); /* returns 0 on failure */ if(gvl_PQsendDescribePortal(conn,StringValueCStr(portal)) == 0) { error = rb_exc_new2(rb_eUnableToSend, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
Asynchronously send command to the server. Does not block. Use in
combination with conn.get_result
.
static VALUE pgconn_send_describe_prepared(VALUE self, VALUE stmt_name) { VALUE error; PGconn *conn = pg_get_pgconn(self); /* returns 0 on failure */ if(gvl_PQsendDescribePrepared(conn,StringValueCStr(stmt_name)) == 0) { error = rb_exc_new2(rb_eUnableToSend, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
Prepares statement sql with name name to be executed later. Sends prepare command asynchronously, and returns immediately. On failure, it raises a PG::Error.
param_types
is an optional parameter to specify the Oids of
the types of the parameters.
If the types are not specified, they will be inferred by PostgreSQL. Instead of specifying type oids, it's recommended to simply add explicit casts in the query to ensure that the right type is used.
For example: “SELECT $1::int”
PostgreSQL bind parameters are represented as $1, $1, $2, etc., inside the SQL query.
static VALUE pgconn_send_prepare(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn(self); int result; VALUE name, command, in_paramtypes; VALUE param; VALUE error; int i = 0; int nParams = 0; Oid *paramTypes = NULL; rb_scan_args(argc, argv, "21", &name, &command, &in_paramtypes); Check_Type(name, T_STRING); Check_Type(command, T_STRING); if(! NIL_P(in_paramtypes)) { Check_Type(in_paramtypes, T_ARRAY); nParams = (int)RARRAY_LEN(in_paramtypes); paramTypes = ALLOC_N(Oid, nParams); for(i = 0; i < nParams; i++) { param = rb_ary_entry(in_paramtypes, i); if(param == Qnil) paramTypes[i] = 0; else paramTypes[i] = NUM2UINT(param); } } result = gvl_PQsendPrepare(conn, StringValueCStr(name), StringValueCStr(command), nParams, paramTypes); xfree(paramTypes); if(result == 0) { error = rb_exc_new2(rb_eUnableToSend, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
Sends SQL query request specified by sql to PostgreSQL for asynchronous processing, and immediately returns. On failure, it raises a PG::Error.
params
is an optional array of the bind parameters for the SQL
query. Each element of the params
array may be either:
a hash of the form: {:value => String (value of bind parameter) :type => Fixnum (oid of type of bind parameter) :format => Fixnum (0 for text, 1 for binary) } or, it may be a String. If it is a string, that is equivalent to the hash: { :value => <string value>, :type => 0, :format => 0 }
PostgreSQL bind parameters are represented as $1, $1, $2, etc., inside the
SQL query. The 0th element of the params
array is bound to $1,
the 1st element is bound to $2, etc. nil
is treated as
NULL
.
If the types are not specified, they will be inferred by PostgreSQL. Instead of specifying type oids, it's recommended to simply add explicit casts in the query to ensure that the right type is used.
For example: “SELECT $1::int”
The optional result_format
should be 0 for text results, 1 for
binary.
type_map can be a PG::TypeMap derivation (such as PG::BasicTypeMapForQueries). This will type cast the params form various Ruby types before transmission based on the encoders defined by the type map. When a type encoder is used the format and oid of a given bind parameter are retrieved from the encoder instead out of the hash form described above.
static VALUE pgconn_send_query(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn(self); int result; VALUE command, in_res_fmt; VALUE error; int nParams; int resultFormat; struct query_params_data paramsData; rb_scan_args(argc, argv, "13", &command, ¶msData.params, &in_res_fmt, ¶msData.typemap); paramsData.with_types = 1; Check_Type(command, T_STRING); /* If called with no parameters, use PQsendQuery */ if(NIL_P(paramsData.params)) { if(gvl_PQsendQuery(conn,StringValueCStr(command)) == 0) { error = rb_exc_new2(rb_eUnableToSend, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; } /* If called with parameters, and optionally result_format, * use PQsendQueryParams */ pgconn_query_assign_typemap( self, ¶msData ); resultFormat = NIL_P(in_res_fmt) ? 0 : NUM2INT(in_res_fmt); nParams = alloc_query_params( ¶msData ); result = gvl_PQsendQueryParams(conn, StringValueCStr(command), nParams, paramsData.types, (const char * const *)paramsData.values, paramsData.lengths, paramsData.formats, resultFormat); free_query_params( ¶msData ); if(result == 0) { error = rb_exc_new2(rb_eUnableToSend, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
Execute prepared named statement specified by statement_name asynchronously, and returns immediately. On failure, it raises a PG::Error.
params
is an array of the optional bind parameters for the SQL
query. Each element of the params
array may be either:
a hash of the form: {:value => String (value of bind parameter) :format => Fixnum (0 for text, 1 for binary) } or, it may be a String. If it is a string, that is equivalent to the hash: { :value => <string value>, :format => 0 }
PostgreSQL bind parameters are represented as $1, $1, $2, etc., inside the
SQL query. The 0th element of the params
array is bound to $1,
the 1st element is bound to $2, etc. nil
is treated as
NULL
.
The optional result_format
should be 0 for text results, 1 for
binary.
type_map can be a PG::TypeMap derivation (such as PG::BasicTypeMapForQueries). This will type cast the params form various Ruby types before transmission based on the encoders defined by the type map. When a type encoder is used the format and oid of a given bind parameter are retrieved from the encoder instead out of the hash form described above.
static VALUE pgconn_send_query_prepared(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn(self); int result; VALUE name, in_res_fmt; VALUE error; int nParams; int resultFormat; struct query_params_data paramsData; rb_scan_args(argc, argv, "13", &name, ¶msData.params, &in_res_fmt, ¶msData.typemap); paramsData.with_types = 0; Check_Type(name, T_STRING); if(NIL_P(paramsData.params)) { paramsData.params = rb_ary_new2(0); resultFormat = 0; } pgconn_query_assign_typemap( self, ¶msData ); resultFormat = NIL_P(in_res_fmt) ? 0 : NUM2INT(in_res_fmt); nParams = alloc_query_params( ¶msData ); result = gvl_PQsendQueryPrepared(conn, StringValueCStr(name), nParams, (const char * const *)paramsData.values, paramsData.lengths, paramsData.formats, resultFormat); free_query_params( ¶msData ); if(result == 0) { error = rb_exc_new2(rb_eUnableToSend, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
The number is formed by converting the major, minor, and revision numbers into two-decimal-digit numbers and appending them together. For example, version 7.4.2 will be returned as 70402, and version 8.1 will be returned as 80100 (leading zeroes are not shown). Zero is returned if the connection is bad.
static VALUE pgconn_server_version(VALUE self) { return INT2NUM(PQserverVersion(pg_get_pgconn(self))); }
Sets the client encoding to the encoding String.
static VALUE pgconn_set_client_encoding(VALUE self, VALUE str) { PGconn *conn = pg_get_pgconn( self ); Check_Type(str, T_STRING); if ( (PQsetClientEncoding(conn, StringValueCStr(str))) == -1 ) { rb_raise(rb_ePGerror, "invalid encoding name: %s",StringValueCStr(str)); } #ifdef M17N_SUPPORTED pgconn_set_internal_encoding_index( self ); #endif return Qnil; }
If Ruby has its Encoding.default_internal set, set PostgreSQL's
client_encoding to match. Returns the new Encoding, or nil
if
the default internal encoding wasn't set.
static VALUE pgconn_set_default_encoding( VALUE self ) { PGconn *conn = pg_get_pgconn( self ); rb_encoding *enc; const char *encname; if (( enc = rb_default_internal_encoding() )) { encname = pg_get_rb_encoding_as_pg_encoding( enc ); if ( PQsetClientEncoding(conn, encname) != 0 ) rb_warn( "Failed to set the default_internal encoding to %s: '%s'", encname, PQerrorMessage(conn) ); pgconn_set_internal_encoding_index( self ); return rb_enc_from_encoding( enc ); } else { pgconn_set_internal_encoding_index( self ); return Qnil; } }
Sets connection's verbosity to verbosity and returns the previous setting. Available settings are:
-
PQERRORS_TERSE
-
PQERRORS_DEFAULT
-
PQERRORS_VERBOSE
static VALUE pgconn_set_error_verbosity(VALUE self, VALUE in_verbosity) { PGconn *conn = pg_get_pgconn(self); PGVerbosity verbosity = NUM2INT(in_verbosity); return INT2FIX(PQsetErrorVerbosity(conn, verbosity)); }
See set_notice_receiver for the desription of what this and the notice_processor methods do.
This function takes a new block to act as the notice processor and returns
the Proc object previously set, or nil
if it was previously
the default. The block should accept a single String object.
If you pass no arguments, it will reset the handler to the default.
static VALUE pgconn_set_notice_processor(VALUE self) { VALUE proc, old_proc; t_pg_connection *this = pg_get_connection_safe( self ); /* If default_notice_processor is unset, assume that the current * notice processor is the default, and save it to a global variable. * This should not be a problem because the default processor is * always the same, so won't vary among connections. */ if(default_notice_processor == NULL) default_notice_processor = PQsetNoticeProcessor(this->pgconn, NULL, NULL); old_proc = this->notice_receiver; if( rb_block_given_p() ) { proc = rb_block_proc(); PQsetNoticeProcessor(this->pgconn, gvl_notice_processor_proxy, (void *)self); } else { /* if no block is given, set back to default */ proc = Qnil; PQsetNoticeProcessor(this->pgconn, default_notice_processor, NULL); } this->notice_receiver = proc; return old_proc; }
Notice and warning messages generated by the server are not returned by the
query execution functions, since they do not imply failure of the query.
Instead they are passed to a notice handling function, and execution
continues normally after the handler returns. The default notice handling
function prints the message on stderr
, but the application can
override this behavior by supplying its own handling function.
For historical reasons, there are two levels of notice handling, called the notice receiver and notice processor. The default behavior is for the notice receiver to format the notice and pass a string to the notice processor for printing. However, an application that chooses to provide its own notice receiver will typically ignore the notice processor layer and just do all the work in the notice receiver.
This function takes a new block to act as the handler, which should accept
a single parameter that will be a PG::Result
object, and returns the Proc object previously set, or nil
if
it was previously the default.
If you pass no arguments, it will reset the handler to the default.
Note: The result
passed to the block should
not be used outside of the block, since the corresponding C object could be
freed after the block finishes.
static VALUE pgconn_set_notice_receiver(VALUE self) { VALUE proc, old_proc; t_pg_connection *this = pg_get_connection_safe( self ); /* If default_notice_receiver is unset, assume that the current * notice receiver is the default, and save it to a global variable. * This should not be a problem because the default receiver is * always the same, so won't vary among connections. */ if(default_notice_receiver == NULL) default_notice_receiver = PQsetNoticeReceiver(this->pgconn, NULL, NULL); old_proc = this->notice_receiver; if( rb_block_given_p() ) { proc = rb_block_proc(); PQsetNoticeReceiver(this->pgconn, gvl_notice_receiver_proxy, (void *)self); } else { /* if no block is given, set back to default */ proc = Qnil; PQsetNoticeReceiver(this->pgconn, default_notice_receiver, NULL); } this->notice_receiver = proc; return old_proc; }
To enter single-row mode, call this method immediately after a successful call of #send_query (or a sibling function). This mode selection is effective only for the currently executing query. Then call #get_result repeatedly, until it returns nil.
Each (but the last) received Result has exactly one row and a Result#result_status of PGRES_SINGLE_TUPLE. The last Result has zero rows and is used to indicate a successful execution of the query. All of these Result objects will contain the same row description data (column names, types, etc) that an ordinary Result object for the query would have.
Caution: While processing a query, the server may return some rows and then encounter an error, causing the query to be aborted. Ordinarily, pg discards any such rows and reports only the error. But in single-row mode, those rows will have already been returned to the application. Hence, the application will see some Result objects followed by an Error raised in get_result. For proper transactional behavior, the application must be designed to discard or undo whatever has been done with the previously-processed rows, if the query ultimately fails.
Example:
conn.send_query( "your SQL command" ) conn.set_single_row_mode loop do res = conn.get_result or break res.check res.each do |row| # do something with the received row end end
static VALUE pgconn_set_single_row_mode(VALUE self) { PGconn *conn = pg_get_pgconn(self); VALUE error; if( PQsetSingleRowMode(conn) == 0 ) { error = rb_exc_new2(rb_ePGerror, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return self; }
Sets the nonblocking status of the connection. In the blocking state, calls
to send_query will block
until the message is sent to the server, but will not wait for the query
results. In the nonblocking state, calls to send_query will return an
error if the socket is not ready for writing. Note: This function does not
affect exec, because that
function doesn't return until the server has processed the query and
returned the results. Returns nil
.
static VALUE pgconn_setnonblocking(self, state) VALUE self, state; { int arg; VALUE error; PGconn *conn = pg_get_pgconn(self); if(state == Qtrue) arg = 1; else if (state == Qfalse) arg = 0; else rb_raise(rb_eArgError, "Boolean value expected"); if(PQsetnonblocking(conn, arg) == -1) { error = rb_exc_new2(rb_ePGerror, PQerrorMessage(conn)); rb_iv_set(error, "@connection", self); rb_exc_raise(error); } return Qnil; }
Returns the socket's file descriptor for this connection.
IO.for_fd()
can be used to build a proper IO object to the
socket. If you do so, you will likely also want to set
autoclose=false
on it to prevent Ruby from closing the socket
to PostgreSQL if it goes out of scope. Alternatively, you can use socket_io, which creates an
IO that's associated with the connection object itself, and so
won't go out of scope until the connection does.
Note: On Windows the file descriptor is not really usable, since it can not be used to build a Ruby IO object.
static VALUE pgconn_socket(VALUE self) { int sd; if( (sd = PQsocket(pg_get_pgconn(self))) < 0) rb_raise(rb_eConnectionBad, "PQsocket() can't get socket descriptor"); return INT2NUM(sd); }
Fetch a memoized IO object created from the Connection's underlying socket. This object can be used for IO.select to wait for events while running asynchronous API calls.
Using this instead of socket
avoids the problem of the underlying connection being closed by Ruby when
an IO created using IO.for_fd(conn.socket)
goes out of scope.
This method can also be used on Windows but requires Ruby-2.0+.
static VALUE pgconn_socket_io(VALUE self) { int sd; int ruby_sd; ID id_autoclose = rb_intern("autoclose="); t_pg_connection *this = pg_get_connection_safe( self ); VALUE socket_io = this->socket_io; if ( !RTEST(socket_io) ) { if( (sd = PQsocket(this->pgconn)) < 0) rb_raise(rb_eConnectionBad, "PQsocket() can't get socket descriptor"); #ifdef _WIN32 ruby_sd = rb_w32_wrap_io_handle((HANDLE)(intptr_t)sd, O_RDWR|O_BINARY|O_NOINHERIT); #else ruby_sd = sd; #endif socket_io = rb_funcall( rb_cIO, rb_intern("for_fd"), 1, INT2NUM(ruby_sd) ); /* Disable autoclose feature, when supported */ if( rb_respond_to(socket_io, id_autoclose) ){ rb_funcall( socket_io, id_autoclose, 1, Qfalse ); } this->socket_io = socket_io; } return socket_io; }
Returns status of connection : CONNECTION_OK or CONNECTION_BAD
static VALUE pgconn_status(VALUE self) { return INT2NUM(PQstatus(pg_get_pgconn(self))); }
Enables tracing message passing between backend. The trace message will be
written to the stream stream, which must implement a method
fileno
that returns a writable file descriptor.
static VALUE pgconn_trace(VALUE self, VALUE stream) { VALUE fileno; FILE *new_fp; int old_fd, new_fd; VALUE new_file; t_pg_connection *this = pg_get_connection_safe( self ); if(rb_respond_to(stream,rb_intern("fileno")) == Qfalse) rb_raise(rb_eArgError, "stream does not respond to method: fileno"); fileno = rb_funcall(stream, rb_intern("fileno"), 0); if(fileno == Qnil) rb_raise(rb_eArgError, "can't get file descriptor from stream"); /* Duplicate the file descriptor and re-open * it. Then, make it into a ruby File object * and assign it to an instance variable. * This prevents a problem when the File * object passed to this function is closed * before the connection object is. */ old_fd = NUM2INT(fileno); new_fd = dup(old_fd); new_fp = fdopen(new_fd, "w"); if(new_fp == NULL) rb_raise(rb_eArgError, "stream is not writable"); new_file = rb_funcall(rb_cIO, rb_intern("new"), 1, INT2NUM(new_fd)); this->trace_stream = new_file; PQtrace(this->pgconn, new_fp); return Qnil; }
Executes a BEGIN
at the start of the block, and a
COMMIT
at the end of the block, or ROLLBACK
if
any exception occurs.
static VALUE pgconn_transaction(VALUE self) { PGconn *conn = pg_get_pgconn(self); PGresult *result; VALUE rb_pgresult; VALUE block_result = Qnil; int status; if (rb_block_given_p()) { result = gvl_PQexec(conn, "BEGIN"); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); block_result = rb_protect(rb_yield, self, &status); if(status == 0) { result = gvl_PQexec(conn, "COMMIT"); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); } else { /* exception occurred, ROLLBACK and re-raise */ result = gvl_PQexec(conn, "ROLLBACK"); rb_pgresult = pg_new_result(result, self); pg_result_check(rb_pgresult); rb_jump_tag(status); } } else { /* no block supplied? */ rb_raise(rb_eArgError, "Must supply block for PG::Connection#transaction"); } return block_result; }
returns one of the following statuses:
PQTRANS_IDLE = 0 (connection idle) PQTRANS_ACTIVE = 1 (command in progress) PQTRANS_INTRANS = 2 (idle, within transaction block) PQTRANS_INERROR = 3 (idle, within failed transaction) PQTRANS_UNKNOWN = 4 (cannot determine status)
static VALUE pgconn_transaction_status(VALUE self) { return INT2NUM(PQtransactionStatus(pg_get_pgconn(self))); }
Returns the connected pgtty. (Obsolete)
static VALUE pgconn_tty(VALUE self) { char *tty = PQtty(pg_get_pgconn(self)); if (!tty) return Qnil; return rb_tainted_str_new2(tty); }
Returns the default TypeMap that is currently set for type casts of query bind parameters.
static VALUE pgconn_type_map_for_queries_get(VALUE self) { t_pg_connection *this = pg_get_connection( self ); return this->type_map_for_queries; }
Set the default TypeMap that is used for type casts of query bind parameters.
typemap
must be a kind of PG::TypeMap .
static VALUE pgconn_type_map_for_queries_set(VALUE self, VALUE typemap) { t_pg_connection *this = pg_get_connection( self ); if ( !rb_obj_is_kind_of(typemap, rb_cTypeMap) ) { rb_raise( rb_eTypeError, "wrong argument type %s (expected kind of PG::TypeMap)", rb_obj_classname( typemap ) ); } Check_Type(typemap, T_DATA); this->type_map_for_queries = typemap; return typemap; }
Returns the default TypeMap that is currently set for type casts of result values.
static VALUE pgconn_type_map_for_results_get(VALUE self) { t_pg_connection *this = pg_get_connection( self ); return this->type_map_for_results; }
Set the default TypeMap that is used for type casts of result values.
typemap
must be a kind of PG::TypeMap .
static VALUE pgconn_type_map_for_results_set(VALUE self, VALUE typemap) { t_pg_connection *this = pg_get_connection( self ); if ( !rb_obj_is_kind_of(typemap, rb_cTypeMap) ) { rb_raise( rb_eTypeError, "wrong argument type %s (expected kind of PG::TypeMap)", rb_obj_classname( typemap ) ); } Check_Type(typemap, T_DATA); this->type_map_for_results = typemap; return typemap; }
Converts an escaped string representation of binary data into binary data —
the reverse of escape_bytea. This is
needed when retrieving bytea
data in text format, but not when
retrieving it in binary format.
static VALUE pgconn_s_unescape_bytea(VALUE self, VALUE str) { unsigned char *from, *to; size_t to_len; VALUE ret; UNUSED( self ); Check_Type(str, T_STRING); from = (unsigned char*)StringValueCStr(str); to = PQunescapeBytea(from, &to_len); ret = rb_str_new((char*)to, to_len); OBJ_INFECT(ret, str); PQfreemem(to); return ret; }
Disables the message tracing.
static VALUE pgconn_untrace(VALUE self) { t_pg_connection *this = pg_get_connection_safe( self ); PQuntrace(this->pgconn); rb_funcall(this->trace_stream, rb_intern("close"), 0); this->trace_stream = Qnil; return Qnil; }
Returns the authenticated user name.
static VALUE pgconn_user(VALUE self) { char *user = PQuser(pg_get_pgconn(self)); if (!user) return Qnil; return rb_tainted_str_new2(user); }
Blocks while waiting for notification(s), or until the optional timeout is reached, whichever comes first. timeout is measured in seconds and can be fractional.
Returns nil
if timeout is reached, the name of the
NOTIFY event otherwise. If used in block form, passes the name of the
NOTIFY event
and the generating pid
into the
block.
Under PostgreSQL 9.0 and later, if the notification is sent with the
optional payload
string, it will be given to the block as the
third argument.
static VALUE pgconn_wait_for_notify(int argc, VALUE *argv, VALUE self) { PGconn *conn = pg_get_pgconn( self ); PGnotify *pnotification; struct timeval timeout; struct timeval *ptimeout = NULL; VALUE timeout_in = Qnil, relname = Qnil, be_pid = Qnil, extra = Qnil; double timeout_sec; rb_scan_args( argc, argv, "01", &timeout_in ); if ( RTEST(timeout_in) ) { timeout_sec = NUM2DBL( timeout_in ); timeout.tv_sec = (time_t)timeout_sec; timeout.tv_usec = (suseconds_t)( (timeout_sec - (long)timeout_sec) * 1e6 ); ptimeout = &timeout; } pnotification = (PGnotify*) wait_socket_readable( conn, ptimeout, notify_readable); /* Return nil if the select timed out */ if ( !pnotification ) return Qnil; relname = rb_tainted_str_new2( pnotification->relname ); PG_ENCODING_SET_NOCHECK( relname, ENCODING_GET(self) ); be_pid = INT2NUM( pnotification->be_pid ); #ifdef HAVE_ST_NOTIFY_EXTRA if ( *pnotification->extra ) { extra = rb_tainted_str_new2( pnotification->extra ); PG_ENCODING_SET_NOCHECK( extra, ENCODING_GET(self) ); } #endif PQfreemem( pnotification ); if ( rb_block_given_p() ) rb_yield_values( 3, relname, be_pid, extra ); return relname; }