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2021-04-02 閱讀量: 420
mysql如何將縱表轉(zhuǎn)為橫表?

問:

mysql如何將縱表轉(zhuǎn)為橫表?



答:

主要是用case....when實(shí)現(xiàn),例如如何轉(zhuǎn)化下圖:




select name as '姓名',

sum(case course when '語文' then score else 0 end) as '語文',

sum(case course when '數(shù)學(xué)' then score else 0 end) as '數(shù)學(xué)',

sum(case course when '物理' then score else 0 end) as '物理'

from couses_table group by name;


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