PDO->exec()

Execute an SQL statement and return the number of affected rows ()

PDO {
  int 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().

Parameters

statement: The SQL statement to prepare and execute.

Return Values

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.

Warning:

This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE, such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

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():

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<?php

$db->exec() or die($db->errorInfo());
?>

Examples

Example 1760. Issuing a DELETE statement

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

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<?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");
?>

The above example will output:

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Deleted 1 rows.

See Also

PDO->prepare()

PDO->query()

PDOStatement->execute()

If you do this: $res = $dbh->query("SELECT * FROM sessions WHERE session_id = '$p_sessID'"); $l_records = $res->fetch(PDO::FETCH_ASSOC); if( $l_records ) { // ...update session-data $l_theQuery = "UPDATE sessions SET session_expires='$newExp', session_data='$p_sessData' WHERE session_id='$p_sessID'"; echo $l_theQuery; $l_stmt = $this->db->prepare($l_theQuery); if ( $l_stmt ) { $l_rows = $l_stmt->execute(); } } You will get nothing. But do this: $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING); Prior to the code above, you will get this: "PDO::prepare(): SQLSTATE[HY000]: General error: 2014 Cannot execute queries while other unbuffered queries are active. Consider using PDOStatement::fetchAll(). Alternatively, if your code is only ever going to run against mysql, you may enable query buffering by setting the PDO::MYSQL_ATTR_USE_BUFFERED_QUERY attribute." So, instead of fetch(), use fetchAll(), it will make you less insane. Incidentally, the INSERT statement that I was issuing, if the record that I needed to update didn't yet exist, after the initial fetch() command worked perfectly. Changing to fetchAll() fixed it.

PDO->exec()

Execute an SQL statement and return the number of affected rows ()

Parameters

Return Values

Examples

Example 1760. Issuing a DELETE statement

Code Examples / Notes » pdo_exec

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