What does this SQL query mean?

Question

MySQL

Hello,
I have this line of SQL code:

CREATE DATABASE /*!32312 IF NOT EXISTS*/ `_mo` /*!40100 DEFAULT CHARACTER SET latin1 */;

I'm interested in the 2 parts between the characters /* */
What does that mean? More specifically, what do the numbers with the "!" sign mean:
!32312
!40100 Many
thanks in advance!

Answer 1

/*!32312 */ - text inside comment is used if mysql version is higher or equal to specified
For MySQL below 3.23.12 the full line will be
For versions from 3.23.12 to 4.0.xx:
For 4.1.0 and higher

CREATE DATABASE IF NOT EXISTS `_mo` DEFAULT CHARACTER SET latin1;