Selects "full" vacuum, which can reclaim more space, but takes much longer and exclusively locks the table. This method also requires extra disk space, since it writes a new copy of the table and doesn't release the old copy until the operation is complete. Usually this should only be used when a significant amount of space needs to be reclaimed from within the table.
To use a literal instance of a special character in a regular expression, precede it by two backslash (\) characters. The MySQL parser interprets one of the backslashes, and the regular expression library interprets the other. For example, to match the string 1+2 that contains the special + character, only the last of the following regular expressions is the correct one:mysql> SELECT REGEXP_LIKE('1+2', '1+2'); -> 0 mysql> SELECT REGEXP_LIKE('1+2', '1\+2'); -> 0 mysql> SELECT REGEXP_LIKE('1+2', '1\\+2'); -> 1
SET timezone='America/Los_Angeles';