oci_connect

(PHP 5)

oci_connect -- Establishes a connection to the Oracle server

Description

resource oci_connect ( string username, string password [, string db [, string charset [, int session_mode]]] )

oci_connect() returns a connection identifier needed for most other OCI calls. The optional third parameter can either contain the name of the local Oracle instance or the name of the entry in tnsnames.ora to which you want to connect. If the optional third parameter is not specified, PHP uses the environment variables ORACLE_SID (Oracle instance) or TWO_TASK (tnsnames.ora) to determine which database to connect to.

Parameter session_mode is available since version 1.1 and accepts the following values: OCI_DEFAULT, OCI_SYSOPER and OCI_SYSDBA. If either OCI_SYSOPER or OCI_SYSDBA were specified, oci_connect() will try to establish privileged connection using external credentials. Privileged connections are disabled by default. To enable them you need to set oci8.privileged_connect to On.

Note: If you're using PHP with Oracle Instant Client, you can use easy connect naming method described here: http://download-west.oracle.com/docs/cd/B12037_01/network.101/b10775/naming.htm#i498306. Basically this means you can specify "//db_host[:port]/database_name" as database name. But if you want to use the old way of naming you must set either ORACLE_HOME or TNS_ADMIN.

Note: The second and subsequent calls to oci_connect() with the same parameters will return the connection handle returned from the first call. This means that queries issued against one handle are also applied to the other handles, because they are the same handle. This behaviour is demonstrated in Example 1 below. If you require two handles to be transactionally isolated from each other, you should use oci_new_connect() instead.

Using Oracle server version 9.2 and greater, you can indicate charset parameter, which will be used in the new connection. If you're using Oracle server < 9.2, this parameter will be ignored and NLS_LANG environment variable will be used instead.

Example 1. oci_connect() example

<?php
echo "<pre>";
$db "";

$c1 oci_connect("scott""tiger"$db);
$c2 oci_connect("scott""tiger"$db);

function 
create_table($conn
{
  
$stmt oci_parse($conn"create table scott.hallo (test varchar2(64))");
  
oci_execute($stmt);
  echo 
$conn " created table\n\n";
}

function 
drop_table($conn
{
  
$stmt oci_parse($conn"drop table scott.hallo");
  
oci_execute($stmt);
  echo 
$conn " dropped table\n\n";
}

function 
insert_data($conn
{
  
$stmt oci_parse($conn"insert into scott.hallo 
            values('$conn' || ' ' || to_char(sysdate,'DD-MON-YY HH24:MI:SS'))"
);
  
oci_execute($stmtOCI_DEFAULT);
  echo 
$conn " inserted hallo\n\n";
}

function 
delete_data($conn
{
  
$stmt oci_parse($conn"delete from scott.hallo");
  
oci_execute($stmtOCI_DEFAULT);
  echo 
$conn " deleted hallo\n\n";
}

function 
commit($conn
{
  
oci_commit($conn);
  echo 
$conn " committed\n\n";
}

function 
rollback($conn
{
  
oci_rollback($conn);
  echo 
$conn " rollback\n\n";
}

function 
select_data($conn
{
  
$stmt oci_parse($conn"select * from scott.hallo");
  
oci_execute($stmtOCI_DEFAULT);
  echo 
$conn."----selecting\n\n";
  while (
oci_fetch($stmt)) {
    echo 
$conn " [" oci_result($stmt"TEST") . "]\n\n";
  }
  echo 
$conn "----done\n\n";
}

create_table($c1);
insert_data($c1);   // Insert a row using c1
insert_data($c2);   // Insert a row using c2

select_data($c1);   // Results of both inserts are returned
select_data($c2);   

rollback($c1);      // Rollback using c1

select_data($c1);   // Both inserts have been rolled back
select_data($c2);   

insert_data($c2);   // Insert a row using c2
commit($c2);        // Commit using c2

select_data($c1);   // Result of c2 insert is returned

delete_data($c1);   // Delete all rows in table using c1
select_data($c1);   // No rows returned
select_data($c2);   // No rows returned
commit($c1);        // Commit using c1

select_data($c1);   // No rows returned
select_data($c2);   // No rows returned

drop_table($c1);
echo 
"</pre>";
?>

oci_connect() returns FALSE if an error occured.

Note: In PHP versions before 5.0.0 you must use ocilogon() instead. This name still can be used, it was left as the alias of oci_connect() for downwards compatability. This, however, is deprecated and not recommended.

See also oci_pconnect(), oci_new_connect() and oci_close().