SQL 查询 - 获取两个表的不同计数

Question

表 1(student_details)

拥有 532 条数据，每个顾问都有不同的顾问，每个数据都分配给一个顾问，例如

    id advisor
    -- -------
    1  Bala
    2  Shanmugam
    3  Priya
    4 Bala
   etc..

类似表 2：training_details

        id advisor
        -- -------
        1  Bala

       etc..

我尝试了这个查询，这将返回从 t​​able1 单独分配给每个顾问的人数。我只想从两个表中计数并选择顾问

SELECT DISTINCT t1.advisor as advisor,IFNULL(COUNT(t2.advisor), 0) AS total  FROM advisor AS t1 
LEFT JOIN student_details AS t2 ON t1.advisor = t2.advisor AND t2.del!=1 GROUP BY t1.advisor;

同样，我只想加入两个表条目并在 2 列中返回具有相同计数的不同顾问；

Answer 1

SELECT advisor, COUNT(*) as TheCount
FROM
    (
     SELECT advisor FROM table 1
     UNION ALL
     SELECT advisor FROM table 2
     ) AS [TheNames]
GROUP BY advisor

或

SELECT x.advisor, COUNT(x.advisor)
    FROM (SELECT advisor
            FROM table1
          UNION ALL
          SELECT advisor
            FROM table2
         ) x
GROUP BY x.advisor