5.2 MySQL differences compared to ANSI SQL92

We try to make MySQL follow the ANSI SQL standard and the ODBC SQL standard, but in some cases MySQL does some things differently:

• -- is only a comment if followed by a white space. 5.3.7 `--' as the start of a comment.
• For VARCHAR columns, trailing spaces are removed when the value is stored. E Known errors and design deficiencies in MySQL.
• In some cases, CHAR columns are silently changed to VARCHAR columns. 7.6.1 Silent column specification changes.
• Privileges for a table is not automatically revoked when you delete a table. You must explicitly issue a REVOKE to revoke privileges for a table. GRANT.