SQL Server：concat值

Question

我有3列SPRTELE_PHONE_AREA，SPRTELE_PHONE_NUMBER和SPRTELE_PHONE_EXT-前缀，数字和后缀。

我创建了一种情况，如果SPRTELE_PHONE_NUMBER和SPRTELE_PHONE_AREA为空，我只想显示SPRTELE_PHONE_EXT。否则，如果它们不为null，则输出将是带有括号和点的“（prefix）number.ext”。

这是我的代码：

SELECT
    CASE
        WHEN SPRTELE_PHONE_AREA IS NULL AND SPRTELE_PHONE_EXT IS NULL 
           THEN SPRTELE_PHONE_NUMBER
           ELSE CONCAT('(', SPRTELE_PHONE_AREA, ')', SPRTELE_PHONE_NUMBER, '.', SPRTELE_PHONE_EXT)
    END
FROM 
    vcc.sprtele;

问题是输出显示为每条记录的第二种情况：“ CONCAT ...”

问题出在哪里？

示例：前缀= 650，数字= 1234567，扩展名= 890

• 如果prefix和ext为null-> 1234567
• 如果前缀和ext不为空->（650）1234567.890

如果prefix为null而ext不为null-> 1234567.890，反之亦然

Answer 1

您的查询缺少2种情况：
如果前缀为null而ext不为null 和
如果ext为空且前缀不为空。

[{"account":"1","cost":17.009999999999998},{"account":"2","cost":2.25}]
[{"anotheraccount":"a","cost":2}]

Answer 2

如何？

COALESCE(CONCAT('(', SPRTELE_PHONE_AREA, ')', SPRTELE_PHONE_NUMBER, '.', SPRTELE_PHONE_EXT)
        ,CONCAT('(', SPRTELE_PHONE_AREA, ')', SPRTELE_PHONE_NUMBER
        ,CONCAT( SPRTELE_PHONE_NUMBER, '.', SPRTELE_PHONE_EXT)
        ,SPRTELE_PHONE_NUMBER,'')

COALESCE采用第一个非空值。

Answer 3

你在这里

- url: /client-ssl
 static_files: client-ssl
 upload: client-ssl
 application_readable: true

返回：

CREATE TABLE T(
  Prefix VARCHAR(20),
  Num VARCHAR(20),
  Ext VARCHAR(20)
);

INSERT INTO T VALUES
('1', '11', '111'),
(NULL, '22', '222'),
('3', '33', NULL),
(NULL, '44', NULL);

SELECT CONCAT( IIF(Prefix IS NULL, '', CONCAT('(', Prefix, ')')),
               Num,
               IIF(Ext IS NULL, '', CONCAT('.', Ext))
             ) Results
FROM T

Answer 4

此处的关键是将连接到字段值的格式字符（括号和句点）放入ISNULL（）函数内：

+-----------+
|  Results  |
+-----------+
| (1)11.111 |
| 22.222    |
| (3)33     |
| 44        |
+-----------+

结果是：

;WITH Data AS (
    SELECT  1 AS ExampleNumber,
            '555' AS Prefix,
            '1234567' AS PhoneNumber,
            '999' AS Extension
    UNION
    SELECT  2 AS ExampleNumber,
            NULL AS Prefix,
            '1234567' AS PhoneNumber,
            '999' AS Extension
    UNION
    SELECT  3 AS ExampleNumber,
            '555' AS Prefix,
            '1234567' AS PhoneNumber,
            NULL AS Extension
)

SELECT      ISNULL('(' + d.Prefix + ')', '')
                + ISNULL(d.PhoneNumber, '')
                + ISNULL('.' + d.Extension, '')
FROM        Data d
ORDER BY    d.ExampleNumber

如果您将回车符+换行符串联在一起，则此方法还可以用于连接地址1，地址2和地址3，而不会出现空格。