这是我的查询
SELECT currency_code, SUM(
CASE
WHEN TYPE = 'buy'
THEN to_amount
END ) AS BUY, SUM(
CASE
WHEN TYPE = 'sell'
THEN to_amount
END ) AS SELL, SUM(
CASE
WHEN TYPE = 'sell'
THEN rate
END ) AS SELL_RATE, SUM(
CASE
WHEN TYPE = 'buy'
THEN rate
END ) AS BUY_RATE
FROM tb_currency
LEFT JOIN tb_bill ON tb_currency.CURRENCY_ID = tb_bill.CURRENCY_ID
AND tb_bill.TYPE
IN (
'buy', 'sell'
)
输出是
现在我想将 BUY 字段中的值除以 BUY_RATE 字段中的值。我之前尝试过几个查询并收到错误消息“Unknown column type BUY”。 如何解决?
最佳答案
你需要做一个子选择,像这样
SELECT *, (BUY/BUY_RATE) AS DIV_VALUE FROM (
SELECT currency_code, SUM(
CASE
WHEN TYPE = 'buy'
THEN to_amount
END ) AS BUY, SUM(
CASE
WHEN TYPE = 'sell'
THEN to_amount
END ) AS SELL, SUM(
CASE
WHEN TYPE = 'sell'
THEN rate
END ) AS SELL_RATE, SUM(
CASE
WHEN TYPE = 'buy'
THEN rate
END ) AS BUY_RATE
FROM tb_currency
LEFT JOIN tb_bill ON tb_currency.CURRENCY_ID = tb_bill.CURRENCY_ID
AND tb_bill.TYPE
IN (
'buy', 'sell'
)
)
关于mysql - 如何使用mysql查询划分,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/4989976/