SELECT *, IF (LOCATE('검색어', `필드명`) < 20, SUBSTRING(`필드명`, 1, 200), SUBSTRING(`필드명`, LOCATE('검색어', `필드명`) - 20, 200)) AS `저장할가상필드명` FROM `테이블명`
SELECT *, IF (LOCATE('검색어', `필드명`) < 20, SUBSTRING(`필드명`, 1, 200), SUBSTRING(`필드명`, LOCATE('검색어', `필드명`) - 20, 200)) AS `저장할가상필드명` FROM `테이블명`