This function cannot be used with any queries that return results. This includes SELECT, OPTIMIZE TABLE, etc.
(PHP 5 >= 5.1.0, PHP 7, PHP 8, PECL pdo >= 0.1.0)
PDO::exec — Execute an SQL statement and return the number of affected rows
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().
statementThe SQL statement to prepare and execute.
Data inside the query should be properly escaped.
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.
Ця функція може
повертати як логічне false, так і не логічне значення, яке прирівнюється до
false. Докладніше про це описано в розділі Логічні типи даних. Для перевірки
значення, яке повертає ця функція, використовується оператор ===.
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
$db->exec() or die(print_r($db->errorInfo(), true)); // incorrect
?>
Видає помилку рівня E_WARNING, якщо атрибут
PDO::ATTR_ERRMODE дорівнює
PDO::ERRMODE_WARNING.
Викидає PDOException, якщо атрибут
PDO::ATTR_ERRMODE дорівнює
PDO::ERRMODE_EXCEPTION.
Приклад #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");
/* Return number of rows that were deleted */
print "Deleted $count rows.\n";
?>Поданий вище приклад виведе:
Deleted 1 rows.
This function cannot be used with any queries that return results. This includes SELECT, OPTIMIZE TABLE, etc.Note that with MySQL you can detect a DUPLICATE KEY with INSERT (1 = INSERT, 2 = UPDATE) :
<?php
// MySQL specific INSERT UPDATE-like syntax
$sql = <<<SQL
INSERT INTO customers
SET
id = {$pdo->quote($id)},
name = {$pdo->quote($name)},
address = {$pdo->quote($address)}
AS new
ON DUPLICATE KEY UPDATE
name = new.name,
address = new.address
SQL;
$result = $pdo->exec($sql);
if ($result === 1) {
// An INSERT of a new row has be done
} elseif ($result === 2) {
// An UPDATE of an existing row has be done
}It's worth noting here, that - in addition to the hints given in docs up there - using prepare, bind and execute provides more benefits than multiply querying a statement: performance and security!
If you insert some binary data (e.g. image file) into database using INSERT INTO ... then it may boost performance of parsing your statement since it is kept small (a few bytes, only, while the image may be several MiBytes) and there is no need to escape/quote the file's binary data to become a proper string value.
And, finally and for example, if you want to get a more secure PHP application which isn't affectable by SQL injection attacks you _have to_ consider using prepare/execute on every statement containing data (like INSERTs or SELECTs with WHERE-clauses). Separating the statement code from related data using prepare, bind and execute is best method - fast and secure! You don't even need to escape/quote/format-check any data.PDO::eval() might return `false` for some statements (e.g. CREATE TABLE) even if the operation completed successfully, when using PDO_DBLIB and FreeTDS. So it is not a reliable way of testing the op status.
PDO::errorInfo() can be used to test the SQLSTATE error code for '00000' (success) and '01000' (success with warning).
<?php
function execute(PDO $conn, $sql) {
$affected = $conn->exec($sql);
if ($affected === false) {
$err = $conn->errorInfo();
if ($err[0] === '00000' || $err[0] === '01000') {
return true;
}
}
return $affected;
}
?>
PDO::errorInfo(): http://php.net/manual/en/pdo.errorinfo.php
List of SQLSTATE Codes: http://www-01.ibm.com/support/knowledgecenter/SSGU8G_11.70.0/com.ibm.sqls.doc/ids_sqs_0809.htmthis function don't execute multi_query
to get it see SQLITE_EXEC comments there is an pereg function that get all queries and execute all then an return the last one