mysql横表纵表转换

一.横表转纵表

select id,姓名,'语文' as SUBJECT,语文 as 'score' from hb 
UNION
select id,姓名,'数学' as SUBJECT,数学 as 'score' from hb 
UNION
select id,姓名,'英语' as SUBJECT,英语 as 'score' from hb 

二.纵表转横表

select name as '姓名',MAX(CASE `subject` WHEN '语文' then score else 0 end) 语文,
MAX(CASE `subject` WHEN '数学' then score else 0 end) 数学,
MAX(CASE `subject` WHEN '英语' then score else 0 end) 英语 from sb group by name