IF语句时对函数的查询（MSSQL）

我有

我希望创建具有输入参数（如Table.Citizen_id）的函数Table_Citizens，并仅为该id输出结果。 但若Table.Citizen_id=0，那个么函数应该输出所有id的数据。我想知道如何执行这个

SELECT 
    Table.Citizen_id AS ID,
    Citizens.Name as Name,
    Citizens.City as City  
FROM Table 
INNER JOIN Citizens   
ON Table.Citizen_id = Citizens.id
GROUP BY Table.Citizen_id, Citizens.Name,Citizens.City;

---

这不起作用

函数中的查询如下所示：

CREATE FUNCTION dbo.Calls_ABCs(@ABC_id AS INT) 
RETURNS TABLE 
AS 
RETURN 
    SELECT 
    Calls.ABC_id AS ID,
    ABCs.Name as Name,
    ABCs.City as City, 
    COUNT(Calls.Call_start) as Count_Calls, 
    AVG(Calls.Duration) AS AVG_Call_duration,
    MAX(Calls.Duration) AS MAX_Call_duration,
    SUM(Calls.Duration) AS SUM_Call_duration,
    SUM(Calls.Cost) AS SUM_Call_cost,
    AVG(Calls.Cost) AS AVG_Calls_Cost,
FROM Calls 
INNER JOIN ABCs   
ON Calls.ABC_id = ABCs.id WHERE (@ABC_id=0 or Calls.ABC_id = @ABC_id) and  Calls.Call_Start > '2013-03-17'  GROUP BY Calls.ABC_id, ABCs.Name,ABCs.City;

GO 

通常，这是用

NULL

值而不是

0

表示的，因为

NULL

适用于所有数据类型。在这种情况下：

SELECT 
    Table.Citizen_id AS ID,
    Citizens.Name as Name,
    Citizens.City as City  
FROM Table INNER JOIN
     Citizens   
     ON Table.Citizen_id = Citizens.id
where @Id = 0 or table.Citizen_id = @id
GROUP BY Table.Citizen_id, Citizens.Name,Citizens.City;

---

函数中的查询如下所示：

CREATE FUNCTION dbo.Calls_ABCs(@ABC_id AS INT) 
RETURNS TABLE 
AS 
RETURN 
    SELECT 
    Calls.ABC_id AS ID,
    ABCs.Name as Name,
    ABCs.City as City, 
    COUNT(Calls.Call_start) as Count_Calls, 
    AVG(Calls.Duration) AS AVG_Call_duration,
    MAX(Calls.Duration) AS MAX_Call_duration,
    SUM(Calls.Duration) AS SUM_Call_duration,
    SUM(Calls.Cost) AS SUM_Call_cost,
    AVG(Calls.Cost) AS AVG_Calls_Cost,
FROM Calls 
INNER JOIN ABCs   
ON Calls.ABC_id = ABCs.id WHERE (@ABC_id=0 or Calls.ABC_id = @ABC_id) and  Calls.Call_Start > '2013-03-17'  GROUP BY Calls.ABC_id, ABCs.Name,ABCs.City;

GO 

通常，这是用

NULL

值而不是

0

表示的，因为

NULL

适用于所有数据类型。在这种情况下：

SELECT 
    Table.Citizen_id AS ID,
    Citizens.Name as Name,
    Citizens.City as City  
FROM Table INNER JOIN
     Citizens   
     ON Table.Citizen_id = Citizens.id
where @Id = 0 or table.Citizen_id = @id
GROUP BY Table.Citizen_id, Citizens.Name,Citizens.City;

试试这个-

查询：

where @Id is NULL or table.Citizen_id = @Id

CREATE FUNCTION dbo.[udf_getCitizens]
(
      @Citizen_id INT
)
RETURNS @Result TABLE (ID INT, Name VARCHAR(50), City VARCHAR(50)) 
AS
BEGIN

    INSERT INTO @Result(ID, Name, City)
    SELECT DISTINCT
          ID = t.Citizen_id
        , c.Name
        , c.City
    FROM dbo.[Table] t 
    JOIN dbo.Citizens c ON t.Citizen_id = Citizens.id 
    WHERE @Citizen_Id = 0 OR t.Citizen_id = @Citizen_id

    RETURN

END

执行官：

where @Id is NULL or table.Citizen_id = @Id

CREATE FUNCTION dbo.[udf_getCitizens]
(
      @Citizen_id INT
)
RETURNS @Result TABLE (ID INT, Name VARCHAR(50), City VARCHAR(50)) 
AS
BEGIN

    INSERT INTO @Result(ID, Name, City)
    SELECT DISTINCT
          ID = t.Citizen_id
        , c.Name
        , c.City
    FROM dbo.[Table] t 
    JOIN dbo.Citizens c ON t.Citizen_id = Citizens.id 
    WHERE @Citizen_Id = 0 OR t.Citizen_id = @Citizen_id

    RETURN

END

试试这个-

查询：

where @Id is NULL or table.Citizen_id = @Id

CREATE FUNCTION dbo.[udf_getCitizens]
(
      @Citizen_id INT
)
RETURNS @Result TABLE (ID INT, Name VARCHAR(50), City VARCHAR(50)) 
AS
BEGIN

    INSERT INTO @Result(ID, Name, City)
    SELECT DISTINCT
          ID = t.Citizen_id
        , c.Name
        , c.City
    FROM dbo.[Table] t 
    JOIN dbo.Citizens c ON t.Citizen_id = Citizens.id 
    WHERE @Citizen_Id = 0 OR t.Citizen_id = @Citizen_id

    RETURN

END

执行官：

where @Id is NULL or table.Citizen_id = @Id

CREATE FUNCTION dbo.[udf_getCitizens]
(
      @Citizen_id INT
)
RETURNS @Result TABLE (ID INT, Name VARCHAR(50), City VARCHAR(50)) 
AS
BEGIN

    INSERT INTO @Result(ID, Name, City)
    SELECT DISTINCT
          ID = t.Citizen_id
        , c.Name
        , c.City
    FROM dbo.[Table] t 
    JOIN dbo.Citizens c ON t.Citizen_id = Citizens.id 
    WHERE @Citizen_Id = 0 OR t.Citizen_id = @Citizen_id

    RETURN

END

---

谢谢对不起，我重写了我的帖子。也许是不清楚。当id=0时，我需要为所有id和其他地方的当前id输出f。@user2377214。这就是此查询的作用。再次感谢，但这在SQL SERVER 2012上不起作用。0返回空值。声明@ID INT SELECT@ID=5 SELECT*FROM dbo.udf_getCitizens（@ID）@user2377214。这大概是因为id为5的记录在“2013-03-17”之后没有记录。当您硬编码“5”并在函数外部运行它时，查询是否返回任何内容？“其中@Id为NULL或table.Citizen_Id=@Id”。我忘了这个把戏叫什么了？那它为什么有效呢？谢谢。对不起，我重写了我的帖子。也许是不清楚。当id=0时，我需要为所有id和其他地方的当前id输出f。@user2377214。这就是此查询的作用。再次感谢，但这在SQL SERVER 2012上不起作用。0返回空值。声明@ID INT SELECT@ID=5 SELECT*FROM dbo.udf_getCitizens（@ID）@user2377214。这大概是因为id为5的记录在“2013-03-17”之后没有记录。当您硬编码“5”并在函数外部运行它时，查询是否返回任何内容？“其中@Id为NULL或table.Citizen_Id=@Id”。我忘了这个把戏叫什么了？为什么它能工作？谢谢，但是如果@Citizen\u id=0 dbo。[udf\u getCitizens]应该只为所选id返回id=t.Citizen\u id，用于所有其他id。谢谢，但是如果@Citizen\u id=0 dbo。[udf\u getCitizens]应该只为所选id返回id=t.Citizen\u id。