联合问题以获得总数

Question

如何通过MySql中的查询计算2个select语句的UNION总记录？

(select name, phone from table1) UNION (select name, phone from table2)

Answer 1

您可以使用派生表：

SELECT COUNT(*)
FROM (
  (select name, phone from table1) 
  UNION 
  (select name, phone from table2)
  ) AS combined_table

UPD：这是fiddle

Answer 2

这是你想要的吗？你的问题不明确。

SELECT COUNT(*) as TotalRecordCount
FROM
     (select name, phone from table1
          UNION 
     select name, phone from table2) as UnionTable

Answer 3

您可以执行类似

的操作

SELECT COUNT(*) FROM
(
    (select name, phone from table1) UNION (select name, phone from table2)  
)