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

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

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

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

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

我很快想到了:

Select (select count(*) from Table1) as Count1, (select count(*) from Table2) as Count2

注意:我在SQL Server中测试了这个，所以从Dual是不必要的(因此存在差异)。