Полезные запросы в MySQL

SELECT SUBSTRING(`field`, 1, (POSITION("-" IN `field`) -1)) AS `new_field` FROM  `table`

UPDATE `table` SET `field` = REPLACE(`field`, 'старый текст', 'новый текст')

SELECT TIMESTAMPDIFF(YEAR, `birth_date`, CURDATE()) AS `age` FROM `table`

SELECT TIMESTAMPDIFF(YEAR, CONCAT_WS('-', `year`, `months`, `day`), CURDATE()) AS `age` FROM `table`