SELECT
IF (
LOCATE('familyKey', link, 1) = 0,
NULL,
SUBSTRING(
link,
LOCATE('familyKey', link, 1) + LENGTH('familyKey') + 1,
IF (
LOCATE(
'&',
link,
LOCATE('familyKey', link, 1)
) = 0,
LENGTH(link),
LOCATE(
'&',
link,
LOCATE('familyKey', link, 1)
) - (
LOCATE('familyKey', link, 1) + LENGTH('familyKey') + 1
)
)
)
) familyKey
FROM
illustrations; 最佳答案
