For VARCHAR columns, trailing spaces are removed when the value is stored. (This is fixed in MySQL 5.0.3). See Section B.5.8, “Known Issues in MySQL”.

In some cases, CHAR columns are silently converted to VARCHAR columns when you define a table or alter its structure. (This no longer occurs as of MySQL 5.0.3). See Section 12.1.10.1, “Silent Column Specification Changes”.

There are several differences between the MySQL and standard SQL privilege systems. For example, in MySQL, privileges for a table are not automatically revoked when you delete a table. You must explicitly issue a REVOKE statement to revoke privileges for a table. For more information, see Section 12.4.1.5, “REVOKE Syntax”.

The CAST() function does not support cast to REAL or BIGINT. See Section 11.9, “Cast Functions and Operators”.

Standard SQL requires that a HAVING clause in a SELECT statement be able to refer to columns in the GROUP BY clause. This cannot be done before MySQL 5.0.2.