PDO::exec --
Execute an SQL statement and return the number of affected rows
Описание
int PDO::exec ( string statement )
PDO::exec() 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 statement that you need to issue multiple times, prepare
a PDOStatement object with PDO::prepare() and issue
the statement with PDOStatement::execute().
Список параметров
statement
The SQL statement to prepare and execute.
Возвращаемые значения
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.
Внимание
Эта функция
может возвращать как логическое значение FALSE, так и не относящееся к логическому типу
значение, которое приводится к FALSE, например, 0 или
"". За более подробной информации обратитесь к разделу Булев тип. Используйте оператор === для проверки значения,
возвращаемого этой функцией.
The following example incorrectly relies on the return value of
PDO::exec(), wherein a statement that affected 0 rows
results in a call to die():
<?php $db->exec() or die($db->errorInfo()); ?>
Примеры
Пример 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("Deleted $count rows.\n"); ?>