(no version information, might be only in CVS)
PDO::exec -- Execute an SQL statement and return the number of affected rows警告 |
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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().
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.