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phpmysqltagsenumerate

Enumerating tables used in mysql query?


Is there any way to enumerate tables used in mysql query?

Lets say I have query :

SELECT * FROM   db_people.people_facts pf
INNER JOIN db_system.connections sm ON sm.source_id = pf.object_id
INNER JOIN db_people.people p ON sm.target_id = p.object_id
ORDER BY pf.object_id DESC

And I want in return array:

$tables = array(
[0] => 'db_people.people_facts',
[1] => 'db_system.connections',
[2] => 'db_people.people',
);

Solution

  • The solution marked as good will return only the result tables. But if you do the next query it will fail:

    SELECT users.* FROM users, cats, dogs WHERE users.id = cats.user_id
    

    Will return only users and not cats and dogs tables.

    The best solution is find a good parser, another solution is using REGEX and EXPLAIN query (more info in the next link):

    Get mysql tables in a query

    But I think that another good solution is list all tables and search them inside the query, you can cache the list of tables.

    EDIT: When searching for tables, better use a preg like:

    // (`|'|"| )table_name(\1|$)
    if(preg_match('/(`|\'|"| )table_name(\1|$)/i', $query))
        // found
    

    If not, it can return false positives with for example "table_name2", "table_name3"... table_name will return FOUND two times.