如何为select添加的子查询返回多列？

SELECT 
    (SELECT column1 FROM table1 WHERE condition) AS column1,
    (SELECT column2 FROM table2 WHERE condition) AS column2,
    ...
FROM table3;

SELECT column1, column2
FROM table1
JOIN (SELECT column3, column4 FROM table2 WHERE condition) AS subquery
ON table1.id = subquery.id;

CREATE TABLE #temp (column1 datatype, column2 datatype);
INSERT INTO #temp
SELECT column1, column2 FROM table1 WHERE condition;

SELECT column1, column2
FROM #temp;