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MySQL check if a table exists without throwing an exception

I don't know the PDO syntax for it, but this seems pretty straight-forward:

$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;

If you're using MySQL 5.0 and later, you could try:

SELECT COUNT(*)
FROM information_schema.tables 
WHERE table_schema = '[database name]' 
AND table_name = '[table name]';

Any results indicate the table exists.

From: http://www.electrictoolbox.com/check-if-mysql-table-exists/


Using mysqli i've created following function. Asuming you have an mysqli instance called $con.

function table_exist($table){
    global $con;
    $table = $con->real_escape_string($table);
    $sql = "show tables like '".$table."'";
    $res = $con->query($sql);
    return ($res->num_rows > 0);
}

Hope it helps.

Warning: as sugested by @jcaron this function could be vulnerable to sqlinjection attacs, so make sure your $table var is clean or even better use parameterised queries.


This is posted simply if anyone comes looking for this question. Even though its been answered a bit. Some of the replies make it more complex than it needed to be.

For mysql* I used :

if (mysqli_num_rows(
    mysqli_query(
                    $con,"SHOW TABLES LIKE '" . $table . "'")
                ) > 0
        or die ("No table set")
    ){

In PDO I used:

if ($con->query(
                   "SHOW TABLES LIKE '" . $table . "'"
               )->rowCount() > 0
        or die("No table set")
   ){

With this I just push the else condition into or. And for my needs I only simply need die. Though you can set or to other things. Some might prefer the if/ else if/else. Which is then to remove or and then supply if/else if/else.


Here is the my solution that I prefer when using stored procedures. Custom mysql function for check the table exists in current database.

delimiter $$

CREATE FUNCTION TABLE_EXISTS(_table_name VARCHAR(45))
RETURNS BOOLEAN
DETERMINISTIC READS SQL DATA
BEGIN
    DECLARE _exists  TINYINT(1) DEFAULT 0;

    SELECT COUNT(*) INTO _exists
    FROM information_schema.tables 
    WHERE table_schema =  DATABASE()
    AND table_name =  _table_name;

    RETURN _exists;

END$$

SELECT TABLE_EXISTS('you_table_name') as _exists