pg_pconnect
(PHP 4, PHP 5, PHP 7)
pg_pconnect — 打开一个持久的 PostgreSQL 连接
说明
$connection_string
[,
int $connect_type
] ) :
resource
pg_pconnect() 打开一个到 PostgreSQL 数据库的持久连接。返回其它 PostgreSQL 函数所需要的连接资源号。
If a second call is made to pg_pconnect() with the same connection_string
as an existing connection, the existing connection will be returned unless you pass PGSQL_CONNECT_FORCE_NEW
as connect_type
.
要打开持久连接功能,php.ini 中的 pgsql.allow_persistent 参数必须为 "On"(也是默认值)。 最大持久连接数目由 php.ini 中的 pgsql.max_persistent 参数定义(默认为 -1 表示没有限制)。所有连接的数目可由 php.ini 中的 pgsql.max_links 参数设置。
pg_close() 不能关闭由 pg_pconnect() 打开的持久连接。
参数
-
connection_string
-
The
connection_string
can be empty to use all default parameters, or it can contain one or more parameter settings separated by whitespace. Each parameter setting is in the form keyword = value. Spaces around the equal sign are optional. To write an empty value or a value containing spaces, surround it with single quotes, e.g., keyword = 'a value'. Single quotes and backslashes within the value must be escaped with a backslash, i.e., \' and \.The currently recognized parameter keywords are:
host
,hostaddr
,port
,dbname
,user
,password
,connect_timeout
,options
,tty
(ignored),sslmode
,requiressl
(deprecated in favor ofsslmode
), andservice
. Which of these arguments exist depends on your PostgreSQL version. -
connect_type
-
If
PGSQL_CONNECT_FORCE_NEW
is passed, then a new connection is created, even if theconnection_string
is identical to an existing connection.
返回值
PostgreSQL connection resource on success, FALSE
on failure.
范例
Example #1 Using pg_pconnect()
<?php
$dbconn = pg_pconnect("dbname=mary");
//connect to a database named "mary"
$dbconn2 = pg_pconnect("host=localhost port=5432 dbname=mary");
// connect to a database named "mary" on "localhost" at port "5432"
$dbconn3 = pg_pconnect("host=sheep port=5432 dbname=mary user=lamb password=foo");
//connect to a database named "mary" on the host "sheep" with a username and password
$conn_string = "host=sheep port=5432 dbname=test user=lamb password=bar";
$dbconn4 = pg_pconnect($conn_string);
//connect to a database named "test" on the host "sheep" with a username and password
?>