Check if a database table exists using PHP/PDO

Question

I want to check if a table with a specific name exists in a database I\'ve connected to using PHP and PDO.

It has to work on all database backends, like MySQL, SQLi

Answer 1

This seems to work at least with SQLite3 without exceptions, etc:

        $select =
            "SELECT CASE WHEN EXISTS (SELECT * FROM SQLITE_MASTER WHERE TYPE = 'table' AND NAME = :tableName) THEN 1 ELSE 0 END AS TABLE_EXISTS;";

Answer 2

Before I go on, I do realise this is a MySQL-specific solution.

While all the solutions mentioned here may work, I (personally) like to keep PDO from throwing exceptions (personal preference, that's all).

As such, I use the following to test for table creation instead:

SHOW TABLES LIKE 'some_table_of_mine';

There's no error state generated if the table doesn't exist, you simply get a zero resultset. Works fast and consistently for me.

Answer 3

If you have other major actions to do within the same statement, you can use the e->errorInfo

try{                
    //Your major statements here
}
catch(PDOException $e){
    if($e->errorInfo[1] == 1146){
        //when table doesn't exist
    }      
}

Answer 4

I do a few things in my web apps with CodeIgniter to check that the database exists (and is useful), any of these can work:

@$this->load->database();
$v = @$this->db->version()
$tables = @$this->db->list_tables();

Adding the @ will suppress errors if you have them enabled in your PHP setup, and checking the results of version() and list_tables() can be used to not only determine if your DB is around (but that it's sane too).

Answer 5

You might be able to avoid having to rely on an error by using a query along the lines of "SHOW TABLES LIKE 'your_table'" and then counting the rows. I've been using this method successfully with MySQL and PDO but have yet to test it with other DBs

Answer 6

Do:

select 1 from your_table

and then catch the error. If you don't get any error, but resultset with one column containing "1", then the table exists.