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MySQLの複数のテーブルからのCOUNT（*）

MySQLの複数のテーブルからCOUNT（*）を選択するにはどうすればよいですか？

といった：

SELECT COUNT(*) AS table1Count FROM table1 WHERE someCondition
JOIN?? 
SELECT COUNT(*) AS table2Count FROM table2 WHERE someCondition
CROSS JOIN? subqueries?
SELECT COUNT(*) AS table3Count FROM table3 WHERE someCondition

編集：

目標はこれを返すことです：

+-------------+-------------+-------------+
| table1Count | table2Count | table3Count |
+-------------+-------------+-------------+
| 14          | 27          | 0           |
+-------------+-------------+-------------+
mysqlcount
40
bcmcfc

TableCountごとに1つのサブクエリを使用して、サブクエリを使用してそれを行うことができます。

SELECT
  (SELECT COUNT(*) FROM table1 WHERE someCondition) as table1Count, 
  (SELECT COUNT(*) FROM table2 WHERE someCondition) as table2Count,
  (SELECT COUNT(*) FROM table3 WHERE someCondition) as table3Count
90
Julien Hoarau

サブクエリでこれを行うことができます、例えば：

select (SELECT COUNT(*) FROM table1 WHERE someCondition) as table1Count, 
       (SELECT COUNT(*) FROM table2 WHERE someCondition) as table2Count
11
RedFilter

UNIONを使用できます

  SELECT COUNT(*) FROM table1 WHERE someCondition
  UNION
  SELECT COUNT(*) FROM table2 WHERE someCondition
  UNION
  SELECT COUNT(*) FROM table3 WHERE someCondition
5
Interfector

に変更してみてください：

SELECT 
    COUNT(table1.*) as t1,
    COUNT(table2.*) as t2,
    COUNT(table3.*) as t3 
FROM table1 
    LEFT JOIN tabel2 ON condition
    LEFT JOIN tabel3 ON condition
1
Pramendra Gupta