SELECT (SELECT COUNT(*) FROM table1) + (SELECT COUNT(*) FROM table2) FROM dual;

选择 (select count() from tab1 where field like 'value') + (select count() from tab2 where field like 'value') 数

这是我的分享

选项1 -计数从相同的域从不同的表

select distinct(select count(*) from domain1.table1) "count1", (select count(*) from domain1.table2) "count2" 
from domain1.table1, domain1.table2;

选项2 -同一表从不同的域计数

select distinct(select count(*) from domain1.table1) "count1", (select count(*) from domain2.table1) "count2" 
from domain1.table1, domain2.table1;

选项3 -计数从不同的领域为同一表与“联合所有”有行计数

select 'domain 1'"domain", count(*) 
from domain1.table1 
union all 
select 'domain 2', count(*) 
from domain2.table1;

享受SQL，我总是这样做:)

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

作为附加信息，要在SQL Server中完成同样的事情，您只需要删除查询的“FROM dual”部分。

select (select count(*) from tab1) count_1, (select count(*) from tab2) count_2 from dual;