Question

我之前创建了2个视图，如下所示：

CREATE VIEW T22 
AS
    (SELECT anumber, AVG(slevel) 
     FROM SPOSSESSED
     GROUP BY anumber);

CREATE VIEW T23 (anumber, slevel) 
AS
    (SELECT anumber, 0 
     FROM APPLICANT 
     WHERE anumber NOT IN (SELECT anumber FROM SPOSSESSED));

现在，我需要CREATE VIEW，它是上述两个视图的UNION。我尝试了这个完全正常的语句并显示了我想要的结果：

SELECT * 
FROM T22 
UNION 
SELECT * 
FROM T23;

但是当我尝试为此创建一个视图时，它有一个我似乎无法识别的语法错误：

CREATE VIEW T24 
AS 
   (SELECT * 
    FROM T22 
    UNION 
    SELECT * 
    FROM T23);

Answer 1

管理我自己解决问题，opps！

解决方案是删除括号，语法错误消失了：

CREATE VIEW T24 AS SELECT* FROM T22 UNION SELECT * FROM T23;

Answer 2

列的命名方案存在冲突，在这种情况下您无法使用SELECT *。但是，您可以更改anumber并将其别名更改为其他名称。解决问题。

类似的东西：

CREATE VIEW T24
AS
(
        SELECT anumber AS anumber1,
            AVG(slevel)
        FROM T22

        UNION

        SELECT anumber,
            slevel
        FROM T23
        );

Answer 3

表t22和表t23中的数据类型是否匹配？列数是否匹配？请发布您收到的错误。

在CREATE VIEW中需要有关语法错误的帮助

3 个答案: