The ibm_db2.ini file controls many properties related to to pconnect. For example, stale connection handling is configurable.
(PECL ibm_db2 >= 1.0.0)
db2_pconnect — Returns a persistent connection to a database
$database
, string $username
, string $password
, array $options = ?
) : resourceReturns a persistent connection to an IBM DB2 Universal Database, IBM Cloudscape, or Apache Derby database.
For more information on persistent connections, refer to 数据库持久连接.
Calling db2_close() on a persistent connection always
returns true, but the underlying DB2 client connection remains open and
waiting to serve the next matching db2_pconnect()
request.
Users running version 1.9.0 or later of ibm_db2 should be aware that the extension will perform a transaction rollback on persistent connections at the end of a request, thus ending the transaction. This prevents the transaction block from carrying over to the next request which uses that connection if script execution ends before the transaction block does.
databaseThe database alias in the DB2 client catalog.
usernameThe username with which you are connecting to the database.
passwordThe password with which you are connecting to the database.
optionsAn associative array of connection options that affect the behavior of the connection, where valid array keys include:
autocommit
Passing the DB2_AUTOCOMMIT_ON value turns
autocommit on for this connection handle.
Passing the DB2_AUTOCOMMIT_OFF value turns
autocommit off for this connection handle.
DB2_ATTR_CASE
Passing the DB2_CASE_NATURAL value specifies
that column names are returned in natural case.
Passing the DB2_CASE_LOWER value specifies
that column names are returned in lower case.
Passing the DB2_CASE_UPPER value specifies
that column names are returned in upper case.
CURSOR
Passing the DB2_FORWARD_ONLY value specifies a
forward-only cursor for a statement resource. This is the default
cursor type and is supported on all database servers.
Passing the DB2_SCROLLABLE value specifies a
scrollable cursor for a statement resource. This mode enables
random access to rows in a result set, but currently is supported
only by IBM DB2 Universal Database.
The following new option is available in ibm_db2 version 1.7.0 and later.
trustedcontextPassing the DB2_TRUSTED_CONTEXT_ENABLE value turns trusted context on for this connection handle. This parameter cannot be set using db2_set_option().
This key works only if the database is cataloged (even if the database is local), or if you specify the full DSN when you create the connection.
To catalog the database, use following commands:
db2 catalog tcpip node loopback remote <SERVERNAME> server <SERVICENAME> db2 catalog database <LOCALDBNAME> as <REMOTEDBNAME> at node loopback db2 "update dbm cfg using svcename <SERVICENAME>" db2set DB2COMM=TCPIP
The following new i5/OS options are available in ibm_db2 version 1.5.1 and later.
Conflicting connection attributes used in conjunction with persistent connections can produce indeterminate results on i5/OS. Site policies should be establish for all applications using each persistent connection user profile. The default DB2_AUTOCOMMIT_ON is suggested when using persistent connections.
i5_libA character value that indicates the default library that will be used for resolving unqualified file references. This is not valid if the connection is using system naming mode.
i5_naming
DB2_I5_NAMING_ON value turns on DB2 UDB CLI iSeries
system naming mode. Files are qualified using the slash (/) delimiter.
Unqualified files are resolved using the library list for the job.
DB2_I5_NAMING_OFF value turns off DB2 UDB CLI default
naming mode, which is SQL naming. Files are qualified using the period (.)
delimiter. Unqualified files are resolved using either the default library
or the current user ID.
i5_commit
The i5_commit attribute should be set before the
db2_pconnect(). If the value is changed after the
connection has been established, and the connection is to a remote data
source, the change does not take effect until the next successful
db2_pconnect() for the connection handle.
Note:
The php.ini setting
ibm_db2.i5_allow_commit==0 orDB2_I5_TXN_NO_COMMITis the default, but may be overridden with thei5_commitoption.
DB2_I5_TXN_NO_COMMIT - Commitment control is not used.
DB2_I5_TXN_READ_UNCOMMITTED - Dirty reads, nonrepeatable
reads, and phantoms are possible.
DB2_I5_TXN_READ_COMMITTED - Dirty reads are not possible.
Nonrepeatable reads, and phantoms are possible.
DB2_I5_TXN_REPEATABLE_READ - Dirty reads and nonrepeatable
reads are not possible. Phantoms are possible.
DB2_I5_TXN_SERIALIZABLE - Transactions are serializable.
Dirty reads, non-repeatable reads, and phantoms are not possible
i5_query_optimize
DB2_FIRST_IO All queries are optimized with the goal of
returning the first page of output as fast as possible. This goal works well
when the output is controlled by a user who is most likely to cancel the query
after viewing the first page of output data. Queries coded with an
OPTIMIZE FOR nnn ROWS clause honor the goal specified by the clause.
DB2_ALL_IO All queries are optimized with the goal of running
the entire query to completion in the shortest amount of elapsed time. This is a
good option when the output of a query is being written to a file or report, or
the interface is queuing the output data. Queries coded with an OPTIMIZE FOR nnn
ROWS clause honor the goal specified by the clause. This is the default.
i5_dbcs_alloc
DB2_I5_DBCS_ALLOC_ON value turns on DB2 6X allocation scheme
for DBCS translation column size growth.
DB2_I5_DBCS_ALLOC_OFF value turns off DB2 6X allocation scheme
for DBCS translation column size growth.
Note:
The php.ini setting
ibm_db2.i5_dbcs_alloc==0 orDB2_I5_DBCS_ALLOC_OFFis the default, but may be overridden with thei5_dbcs_allocoption.
i5_date_fmt
DB2_I5_FMT_ISO - The International Organization for Standardization
(ISO) date format yyyy-mm-dd is used. This is the default.
DB2_I5_FMT_USA - The United States date format mm/dd/yyyy is used.
DB2_I5_FMT_EUR - The European date format dd.mm.yyyy is used.
DB2_I5_FMT_JIS - The Japanese Industrial Standard date format
yyyy-mm-dd is used.
DB2_I5_FMT_MDY - The date format mm/dd/yyyy is used.
DB2_I5_FMT_DMY - The date format dd/mm/yyyy is used.
DB2_I5_FMT_YMD - The date format yy/mm/dd is used.
DB2_I5_FMT_JUL - The Julian date format yy/ddd is used.
DB2_I5_FMT_JOB - The job default is used.
i5_date_sep
DB2_I5_SEP_SLASH - A slash ( / ) is used as the date separator.
This is the default.
DB2_I5_SEP_DASH - A dash ( - ) is used as the date separator.
DB2_I5_SEP_PERIOD - A period ( . ) is used as the date
separator.
DB2_I5_SEP_COMMA - A comma ( , ) is used as the date separator.
DB2_I5_SEP_BLANK - A blank is used as the date separator.
DB2_I5_SEP_JOB - The job default is used
i5_time_fmt
DB2_I5_FMT_ISO - The International Organization for
Standardization (ISO) time format hh.mm.ss is used. This is the default.
DB2_I5_FMT_USA - The United States time format
hh:mmxx is used, where xx is AM or PM.
DB2_I5_FMT_EUR - The European time format hh.mm.ss
is used.
DB2_I5_FMT_JIS - The Japanese Industrial Standard
time format hh:mm:ss is used.
DB2_I5_FMT_HMS - The hh:mm:ss format is used.
i5_time_sep
DB2_I5_SEP_COLON - A colon ( : ) is used as the time
separator. This is the default.
DB2_I5_SEP_PERIOD - A period ( . ) is used as the time
separator.
DB2_I5_SEP_COMMA - A comma ( , ) is used as the time
separator.
DB2_I5_SEP_BLANK - A blank is used as the time separator.
DB2_I5_SEP_JOB - The job default is used.
i5_decimal_sep
DB2_I5_SEP_PERIOD - A period ( . ) is used as
the decimal separator. This is the default.
DB2_I5_SEP_COMMA - A comma ( , ) is used as the
decimal separator.
DB2_I5_SEP_JOB - The job default is used.
The following new i5/OS option is available in ibm_db2 version 1.8.0 and later.
i5_liblA character value that indicates the library list that will be used for resolving unqualified file references. Specify the library list elements separated by blanks 'i5_libl'=>"MYLIB YOURLIB ANYLIB".
Note:
i5_libl calls qsys2/qcmdexc('cmd',cmdlen), which is only available in i5/OS V5R4 and later.
Returns a connection handle resource if the connection attempt is
successful. db2_pconnect() tries to reuse an existing
connection resource that exactly matches the
database, username, and
password parameters. If the connection attempt fails,
db2_pconnect() returns false.
| 版本 | 说明 |
|---|---|
| ibm_db2 1.9.0 | Active transactions within a persistent connection will be rolled back at the end of each request. |
| ibm_db2 1.8.0 |
The i5_libl option is available for i5/OS
users.
|
| ibm_db2 1.7.0 |
The trustedcontext option is available.
|
| ibm_db2 1.5.1 |
The i5_lib, i5_naming,
i5_commit,
i5_query_optimize,
i5_dbcs_alloc,
i5_date_fmt,
i5_date_sep,
i5_time_fmt, i5_time_sep
and i5_decimal_sep options are available for
i5/OS users.
|
Example #1 A db2_pconnect() example
In the following example, the first call to db2_pconnect() returns a new persistent connection resource. The second call to db2_pconnect() returns a persistent connection resource that simply reuses the first persistent connection resource.
<?php
$database = 'SAMPLE';
$user = 'db2inst1';
$password = 'ibmdb2';
$pconn = db2_pconnect($database, $user, $password);
if ($pconn) {
echo "Persistent connection succeeded.";
}
else {
echo "Persistent connection failed.";
}
$pconn2 = db2_pconnect($database, $user, $password);
if ($pconn) {
echo "Second persistent connection succeeded.";
}
else {
echo "Second persistent connection failed.";
}
?>
以上例程会输出：
Persistent connection succeeded. Second persistent connection succeeded.
Example #2 Using trusted context
The following example shows how to enable trusted context, switch users, and get the current user ID.
<?php
$database = "SAMPLE";
$hostname = "localhost";
$port = 50000;
$authID = "db2inst1";
$auth_pass = "ibmdb2";
$tc_user = "tcuser";
$tc_pass = "tcpassword";
$dsn = "DATABASE=$database;HOSTNAME=$hostname;PORT=$port;
PROTOCOL=TCPIP;UID=$authID;PWD=$auth_pass;";
$options = array ("trustedcontext" => DB2_TRUSTED_CONTEXT_ENABLE);
$tc_conn = db2_pconnect($dsn, "", "", $options);
if($tc_conn) {
echo "Explicit trusted connection succeeded.\n";
if(db2_get_option($tc_conn, "trustedcontext")) {
$userBefore = db2_get_option($tc_conn, "trusted_user");
//Do some work as user 1.
//Switching to trusted user.
$parameters = array("trusted_user" => $tc_user,
"trusted_password" => $tcuser_pass);
$res = db2_set_option ($tc_conn, $parameters, 1);
$userAfter = db2_get_option($tc_conn, "trusted_user");
//Do more work as trusted user.
if($userBefore != $userAfter) {
echo "User has been switched." . "\n";
}
}
db2_close($tc_conn);
}
else {
echo "Explicit trusted connection failed.\n";
}
?>
以上例程会输出：
Explicit trusted connection succeeded. User has been switched.
The ibm_db2.ini file controls many properties related to to pconnect. For example, stale connection handling is configurable.
If You will create db2 connection on IBMi , QSQSRVR job will be created under QSYSWRK subsystem with specified user.
You can ensure it with using db2_pconnect() function.
For example, db2_pconnect('*LOCAL', 'TESTUSR', 'PASSWORD') will bring us QSQSRVR job with TESTUSR user.
If You omit the user, IHS default user is used in the job.