PHP Manual
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PDO::exec

(no version information, might be only in CVS)

PDO::exec --  Execute an SQL statement and return the number of affected rows

说明

int PDO::exec ( string statement )

警告

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。

PDO::exec() prepares and executes an SQL statement in a single function call, returning the number of rows affected by the statement.

PDO::exec() does not return results from a SELECT statement. For a SELECT statement that you only need to issue once during your program, consider issuing PDO::query(). For a SELECT statement that you need to issue multiple times, prepare a PDOStatement object with PDO::prepare() and issue the statement with PDOStatement::execute().

参数

statement

The SQL statement to prepare and execute.

返回值

PDO::exec() returns the number of rows that were modified or deleted by the SQL statement you issued. If no rows were affected, PDO::exec() returns 0.

警告

Do not rely on the return value as an indicator of success. The following example incorrectly relies on the return value of PDO::exec():
<?php
$db->exec() or die($db->errorInfo());
?>
The previous example is incorrect because the SQL statement may legitimately return 0 affected rows, and die() does not distinguish between 0 and FALSE.

例

例子 1. Issuing a DELETE statement

Count the number of rows deleted by a DELETE statement with no WHERE clause.

<?php
$dbh = new PDO('odbc:sample', 'db2inst1', 'ibmdb2');

/* Delete all rows from the FRUIT table */
$count = $dbh->exec("DELETE FROM fruit WHERE colour = 'red'");

/* Return number of rows that were deleted */
print("Return number of rows that were deleted:\n");
print("Deleted $count rows.\n");
?>

上例将输出：

Return number of rows that were deleted:
Deleted 1 rows.

参见

PDO::prepare()
PDO::query()
PDOStatement::execute()



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PDO::errorInfo上一级PDO::getAttribute