我想加入这些表并计算状态是否为'Y'
table1(date, status)
8/23/2015 Y
8/24/2015 Y
8/24/2015 N
table2(date, status)
8/23/2015 Y
8/23/2015 Y
table3(date, status)
8/23/2015 Y
8/25/2015 N
8/25/2015 Y
我期望的结果就像...
DATE count(table1.status) count(table2.status) count(table3.status)
--------- -------------------- -------------------- --------------------
8/23/2015 1 2 1
8/24/2015 1 0 0
8/25/2015 0 0 1