从多个表中选择计数（*） [英] Select count(*) from multiple tables

问题描述

如何从两个具有结果的不同表格（称为tab1和tab2）中选择计数（*）：

  Count_1 Count_2 
 123 456 
  

？

我尝试过：

  Count_1 from schema.tab1 union all select count（*）Count_2 from schema.tab2 
  

但我所有是：

  Count_1 
 123 
 456 
  pre> 
 
解决方案
 
  SELECT（
 SELECT COUNT（*）
 FROM tab1 
）AS count1，
（
 SELECT COUNT（*）
 FROM tab2 
）AS count2 
 FROM dual 
  
 
How can I select count(*) from two different tables (call them tab1 and tab2) having as result:
Count_1   Count_2
123       456
? 

I've tried this:
select count(*) Count_1 from schema.tab1 union all select count(*) Count_2 from schema.tab2
But all I have is:
Count_1
123
456

解决方案
SELECT  (
        SELECT COUNT(*)
        FROM   tab1
        ) AS count1,
        (
        SELECT COUNT(*)
        FROM   tab2
        ) AS count2
FROM    dual


                        
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