(no version information, might be only in CVS)
PDOStatement::rowCount -- Returns the number of rows affected by the last SQL statement警告 |
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PDOStatement::rowCount() returns the number of rows affected by the last DELETE, INSERT, or UPDATE statement executed by the corresponding PDOStatement object.
If the last SQL statement executed by the associated PDOStatement was a SELECT statement, some databases may return the number of rows returned by that statement. However, this behaviour is not guaranteed for all databases and should not be relied on for portable applications.
例子 2. Counting rows returned by a SELECT statement For most databases, PDOStatement::rowCount() does not return the number of rows affected by a SELECT statement. Instead, use PDO::query() to issue a SELECT COUNT(*) statement with the same predicates as your intended SELECT statement, then use PDOStatement::fetchSingle() to retrieve the number of rows that will be returned. Your application can then perform the correct action.
上例将输出:
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