mysql_unbuffered_query
(PHP 4 >= 4.0.6, PHP 5, PECL mysql:1.0)
mysql_unbuffered_query — Send an SQL query to MySQL, without fetching and buffering the result rows
說明
mysql_unbuffered_query() sends a SQL query query to MySQL, without fetching and buffering the result rows automatically, as mysql_query() does. On the one hand, this saves a considerable amount of memory with SQL queries that produce large result sets. On the other hand, you can start working on the result set immediately after the first row has been retrieved: you don't have to wait until the complete SQL query has been performed. When using multiple DB-connects, you have to specify the optional parameter link_identifier .
參數
- query
-
A SQL query
- link_identifier
-
MySQL 的連接識別符。如果沒有指定，預設使用最後被 mysql_connect() 打開的連接。如果沒有找到該連接，函式會嘗試呼叫 mysql_connect() 建立連接並使用它。如果發生意外，沒有找到連接或無法建立連接，系統發出 E_WARNING 級別的警告信息。
Return值
For SELECT, SHOW, DESCRIBE or EXPLAIN statements, mysql_unbuffered_query() returns a resource on success, or FALSE on error.
For other type of SQL statements, UPDATE, DELETE, DROP, etc, mysql_unbuffered_query() returns TRUE on success or FALSE on error.
註釋
Note: The benefits of mysql_unbuffered_query() come at a cost: You cannot use mysql_num_rows() and mysql_data_seek() on a result set returned from mysql_unbuffered_query(). You also have to fetch all result rows from an unbuffered SQL query, before you can send a new SQL query to MySQL.