pg_send_query

发送异步查询 (PHP 4 >= 4.2.0, PHP 5)
bool pg_send_query ( resource connection, string query )
bool pg_send_query ( string query )

说明

pg_send_query()connection 连接发送异步查询。和 pg_query() 不同,它可以向 PostgreSQL 发送多个查询并用 pg_get_result() 依次得到结果。当执行查询时脚本的执行不会被锁定。用 pg_connection_busy() 来检查连接连接是否为忙(即查询正在执行中)。调用 pg_cancel_query() 则有可能取消查询。

尽管用户可以一次发送多个查询,但用户不能通过正忙的连接发送多个查询。如果向正忙的连接发送了查询,则会等待上一条查询结束并丢弃所有结果。

例 1627. 异步查询

<?php
   $dbconn
= pg_connect("dbname=publisher") or die("Could not connect");
   if (!
pg_connection_busy($dbconn)) {
       
pg_send_query($dbconn,"select * from authors; select count(*) from authors;");
   }
   
$res1 = pg_get_result($dbconn);
   echo
"First call to pg_get_result(): $res1\n";
   
$rows1 = pg_num_rows($res1);
   echo
"$res1 has $rows1 records\n\n";
   
$res2 = pg_get_result($dbconn);
   echo
"second call to pg_get_result(): $res2\n";
   
$rows2 = pg_num_rows($res2);
   echo
"$res2 has $rows2 records\n";
?>

上例输出如下:

first call to pg_get_result(): Resource id #3
Resource id #3 has 3 records

second call to pg_get_result(): Resource id #4
Resource id #4 has 1 records

参见 pg_query()pg_cancel_query()pg_get_result()pg_connection_busy()