??????:
????flink??????????????????????????count????????????????
count([all] Expression | distinct Expression1 [,
Expression2])
????????????????????????????distinct??????????????????????????????????????????????
select count(distinct a, b) from mytable??????????????????????
????????????sql????????????????????
codegenexpression. No matching accumulate methods for Aggregation function.
......CountAggFunction with Parameters (Java.lang.String, java.lang.Long)
Flink1.8??1.9????????????????????????????????
