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 a public-domain, 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 use unix domain sockets, a table is given to this new 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 socket".
Table 1. Postmaster and PHP
Postmaster | PHP | Status |
---|---|---|
postmaster & | pg_connect("", "", "", "", "dbname"); | OK |
postmaster -i & | pg_connect("", "", "", "", "dbname"); | OK |
postmaster & | pg_connect("localhost", "", "", "", "dbname"); | 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("localhost", "", "", "", "dbname"); | OK |
One can also establish a connection with the following command: $conn = pg_Connect("host=localhost port=5432 dbname=chris");
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 and end. If the transaction fails the transaction should be closed with abort and rollback.
Example 1. Using Large Objects <?php $database = pg_Connect ("", "", "", "", "jacarta"); pg_exec ($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 ($database, "commit") pg_exec ($database, "end") ?> |