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PHP5中文手册
PDO->sqliteCreateFunction()(No version information available, might be only in CVS) PDO->sqliteCreateFunction() — Registers a User Defined Function for use in SQL statements 说明PDO
bool sqliteCreateFunction
( string $function_name
, callback $callback
[, int $num_args
] )
Warning
本函数是实验性的。本函数的行为,包括函数名称以及其它任何关于本函数的文档可能会在没有通知的情况下随 PHP 以后的发布而改变。使用本函数风险自担。 This method allows you to register a PHP function with SQLite as an UDF (User Defined Function), so that it can be called from within your SQL statements. The UDF can be used in any SQL statement that can call functions, such as SELECT and UPDATE statements and also in triggers. 参数
返回值如果成功则返回 TRUE,失败则返回 FALSE。 范例
Example#1 PDO::sqliteCreateFunction() example
<?php In this example, we have a function that calculates the md5 sum of a string, and then reverses it. When the SQL statement executes, it returns the value of the filename transformed by our function. The data returned in $rows contains the processed result. The beauty of this technique is that you do not need to process the result using a foreach() loop after you have queried for the data. Tip
You can use PDO->sqliteCreateFunction() and PDO->sqliteCreateAggregate() to override SQLite native SQL functions.
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