MERGE
描述
将聚合中间结果进行聚合并计算获得实际结果。
结果的类型与AGGREGATE_FUNCTION一致。
语法
AGGREGATE_FUNCTION_MERGE(agg_state)
举例
mysql [test]>select avg_merge(avg_state(1)) from d_table;
+-------------------------+
| avg_merge(avg_state(1)) |
+-------------------------+
| 1 |
+-------------------------+Keywords
AGG_STATE, MERGE