bcmcfc bcmcfc - 3 months ago 9
MySQL Question

COUNT(*) from multiple tables in MySQL

How do I go about selecting COUNT(*)s from multiple tables in MySQL?

Such as:

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


Edit:

The goal is to return this:

+-------------+-------------+-------------+
| table1Count | table2Count | table3Count |
+-------------+-------------+-------------+
| 14 | 27 | 0 |
+-------------+-------------+-------------+

Answer

You can do it by using subqueries, one subquery for each tableCount :

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
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