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Noticed a small mistake in the MySQL section:

    Error Based:
        AND (SELECT * FROM SOME_EXISTING_TABLE) = 1

Unless SOME_EXISTING_TABLE has no more than one row, that query will fail. See http://dev.mysql.com/doc/refman/5.0/en/comparisons-using-sub...:

"For a comparison of the subquery to a scalar, the subquery must return a scalar."

It's easy to fix: just add LIMIT 1 to the end of the sub-select.

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This document is very useful. I've been doing web app security for a while and I haven't run across some of these techniques before (eg: PROCEDURE ANALYSE()). I didn't realize that PDO_MYSQL allowed for multiple queries by default either (although it makes sense, since historically other RDBMS have supported it).

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mysql> use test Database changed mysql> show tables; Empty set (0.00 sec) mysql> create table test (id int(10) unsigned not null auto_increment, name varchar(10), primary key(id)); Query OK, 0 rows affected (0.13 sec) mysql> insert into test (name) values ("Bob"); Query OK, 1 row affected (0.02 sec) mysql> select * from test; +----+------+ | id | name | +----+------+ | 1 | Bob | +----+------+ 1 row in set (0.00 sec) mysql> select * from test WHERE (select * FROM test) = 1; ERROR 1241 (21000): Operand should contain 2 column(s) mysql> select * from test WHERE (select 1 FROM test) = 1; +----+------+ | id | name | +----+------+ | 1 | Bob | +----+------+ 1 row in set (0.00 sec) mysql> insert into test (name) values ("Frank"); Query OK, 1 row affected (0.00 sec) mysql> select * from test WHERE (select 1 FROM test) = 1; ERROR 1242 (21000): Subquery returns more than 1 row