LXVIII. PostgreSQL functions
Postgres, developed originally in the UC Berkeley Computer Science
Department, pioneered many of the object-relational concepts now
becoming available in some commercial databases. It provides
SQL92/SQL3 language support, transaction integrity, and type
extensibility. PostgreSQL is an open source descendant of this
original Berkeley code.
PostgreSQL is available without cost. The current version is
available at www.PostgreSQL.org.
Since version 6.3 (03/02/1998) PostgreSQL uses unix domain sockets.
A table is shown below describing these new connection possibilities.
This socket will be found in /tmp/.s.PGSQL.5432.
This option can be enabled with the '-i' flag to postmaster
and it's meaning is: "listen on TCP/IP sockets as well as
Unix domain sockets".
Table 1. Postmaster and PHP
| Postmaster | PHP | Status |
|---|
| postmaster & | pg_connect("dbname=MyDbName"); | OK |
| postmaster -i & | pg_connect("dbname=MyDbName"); | OK |
| postmaster & | pg_connect("host=localhost dbname=MyDbName"); |
Unable to connect to PostgreSQL server: connectDB() failed:
Is the postmaster running and accepting TCP/IP (with -i)
connection at 'localhost' on port '5432'? in
/path/to/file.php3 on line 20.
|
| postmaster -i & | pg_connect("host=localhost dbname=MyDbName"); | OK |
One can establish a connection with the following value pairs
set in the command string:
$conn = pg_Connect("host=myHost port=myPort tty=myTTY
options=myOptions dbname=myDB user=myUser password=myPassword ");
The previous syntax of:
$conn = pg_connect ("host", "port", "options", "tty",
"dbname")
has been deprecated.
To use the large object (lo) interface, it is necessary to enclose
it within a transaction block. A transaction block starts with a
begin and if the transaction was valid ends
with commit or end. If the
transaction fails the transaction should be closed with
rollback or abort.
Example 1. Using Large Objects
<?php
$database = pg_Connect ("dbname=jacarta");
pg_exec ($database, "begin");
$oid = pg_locreate ($database);
echo ("$oid\n");
$handle = pg_loopen ($database, $oid, "w");
echo ("$handle\n");
pg_lowrite ($handle, "gaga");
pg_loclose ($handle);
pg_exec ($database, "commit");
?>
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