更新时间:2023-09-28 23:15:10
您可以使用如下查询:
SELECT t1.ID1, t1.YEAR1,
COUNT(CASE WHEN t2.VALUE = 'A' AND t1.YEAR1 > t2.YEAR2 THEN 1 END) AS A,
COUNT(CASE WHEN t2.VALUE = 'B' AND t1.YEAR1 > t2.YEAR2 THEN 1 END) AS B,
COUNT(CASE WHEN t2.VALUE = 'C' AND t1.YEAR1 > t2.YEAR2 THEN 1 END) AS C,
COUNT(CASE WHEN t2.VALUE = 'D' AND t1.YEAR1 > t2.YEAR2 THEN 1 END) AS D,
COUNT(CASE WHEN t2.VALUE = 'E' AND t1.YEAR1 > t2.YEAR2 THEN 1 END) AS E,
COUNT(CASE WHEN t2.VALUE = 'F' AND t1.YEAR1 > t2.YEAR2 THEN 1 END) AS F
FROM Table1 AS t1
LEFT JOIN Table2 AS t2 ON t1.ID1 = t2.ID2
GROUP BY t1.ID1, t1.YEAR1
例如列A
的值是1
,则将其视为T
,否则将其视为F
.
If, e.g. value of column A
is 1
, then this is considered as T
, otherwise it is considered as a F
.