BOOLEAN or TINYINT confusion

Question

I was designing a database for a site where I need to use a boolean datetype to store only 2 states, true or false. I am using MySQL.
While designing the database using phpMyAdmin, I found that I have both the BOOLEAN datatype and the TINYINT datatype.
I went through different articles, some said TINYINT is the same as BOOLEAN, no difference. Some say BOOLEAN is converted into TINYINT in MySQL.

MY question is, if they both are same why do there exist two? There should be only one of them.

Here is the reference to the articles I read:
http://www.careerride.com/MySQL-BOOL-TINYINT-BIT.aspx
http://dev.mysql.com/doc/refman/5.5/en/numeric-type-overview.html

Answer 1

MySQL does not have internal boolean data type. It uses the smallest integer data type - TINYINT.

The BOOLEAN and BOOL are equivalents of TINYINT(1), because they are synonyms.

Try to create this table -

CREATE TABLE table1 (
  column1 BOOLEAN DEFAULT NULL
);

Then run SHOW CREATE TABLE, you will get this output -

CREATE TABLE `table1` (
  `column1` tinyint(1) DEFAULT NULL
)