在一個聲明中使用多個CTE

Question

我想在查詢中使用多個CTE，但是我一直無法使其工作。以下是我想要做的示例：

WITH tbl1 AS 
    (SELECT * 
    FROM tblStuff) 

WITH tbl2 AS 
    (SELECT tbl1.fldStuff1 ... 
    FROM tbl1, tblStuff2) 

    SELECT * 
    FROM tbl2 

Answer 1

WITH tbl1 AS 
    (SELECT * 
    FROM tblStuff), 

tbl2 AS 
    (SELECT tbl1.fldStuff1, tbl1.fldStuff2, tblStuff2.fldStuff1, tblStuff2.fldStuff2 
    FROM tbl1, tblStuff2) 

    SELECT * 
    FROM tbl2 

如果使用多個熱膨脹係數，不需要額外的WITH，單獨用逗號。

Answer 2

您只需指定WITH一次。然後，您可以列出用逗號分隔的其他CTE。例如： -

WITH cte1 AS 
(
    ... 
), 
cte2 AS 
(
    ... 
) 
SELECT ...;