將SELECT查詢的結果存儲為整數，然后在INSERT語句中重用它

Question

我有一個查詢，用於將部門插入department表中。 但是， Address表有一個名為Address_ID的外鍵。 每當我想插入一個新部門時，我還想檢查該地址是否存在，如果不存在，我想創建一個新部門。 如果確實存在，我想找到正確的ID並將其存儲在變量中以備后用。 該變量已在代碼開頭聲明為BIGINT 。

-- If the address already exists, we will select its ID and store it in a variable.
    BEGIN
      SET @Address_ID =
      (
        SELECT TOP 1 [Address_ID]
        FROM [Address]
        WHERE
          [Building] = @Building_Param
          AND [Factory] = @Factory_Param
      )
    END

上面的代碼是較大語句的一部分。 您可以在下面找到完整的代碼。

此段代碼失敗，並顯示以下錯誤消息：

死@ Address_ID-Tabellenvariable muss deklariert werden。

翻譯：

@Address_ID表變量必須聲明。

這是完整的代碼：

/**
 * Inserts a new entry into the department table.
 *
 * @author     Rubbel Die Katz
 */
DECLARE @The_Date DATETIME2
SET @The_Date = GETDATE()

DECLARE @Department_Name_Param NVARCHAR(MAX)
SET @Department_Name_Param = ?

DECLARE @Department_Description_Param NVARCHAR(MAX)
SET @Department_Description_Param = ?

DECLARE @Factory_Param NVARCHAR(MAX)
SET @Factory_Param = ?

DECLARE @Building_Param NVARCHAR(MAX)
SET @Building_Param = ?

DECLARE @Address_ID BIGINT
SET @Address_ID = 0

-- If the address does not exist, we will need to create it automagically.
IF NOT EXISTS (
    SELECT *
    FROM [Address]
    WHERE
      [Building] = @Building_Param
      AND [Factory] = @Factory_Param
)
  BEGIN
    INSERT INTO [Department] (
      [Department_Name],
      [Department_Description],
      [Time_Created],
      [Time_Modified]
    )
    OUTPUT INSERTED.[Address_ID] INTO @Address_ID
    VALUES (
      @Department_Name_Param,
      @Department_Description_Param,
      @The_Date,
      @The_Date
    )
  END
ELSE
-- If the address already exists, we will select its ID and store it in a variable.
    BEGIN
      SET @Address_ID =
      (
        SELECT TOP 1 [Address_ID]
        FROM [Address]
        WHERE
          [Building] = @Building_Param
          AND [Factory] = @Factory_Param
      )
    END

-- If the department does not exist, we will create it using the Address_ID provided by our previous operations.
IF NOT EXISTS (SELECT * FROM [Department] WHERE [Department_Name] = @Department_Name_Param)
BEGIN
  INSERT INTO [Department] (
    [Department_Name],
    [Department_Description],
    [Address_ID],
    [Time_Created],
    [Time_Modified]
  )
  VALUES (
    @Department_Name_Param,
    @Department_Description_Param,
    @Address_ID,
    @The_Date,
    @The_Date
  )
END

我正在使用的表都是空的。

如何從表中獲取BIGINT作為BIGINT而不是表變量？

Answer 1

錯誤非常明顯，在這里，您尚未聲明@Address_ID 。 在批處理開始時，您需要對其進行DECLARE ：

DECLARE @Address_ID TABLE (AddressID BIGINT);

然后，您可以使用以下方法將該值放入數據類型BIGINT的變量中：

DECLARE @Address_ID_BI BIGINT;
SELECT @Address_ID_BI = AddressID
FROM @Address_ID;

該ASSUMES您僅插入一個值。

Answer 2

出現錯誤的原因是您沒有插入地址表並獲得該標識值。

如果您從以下位置更改代碼段：

INSERT INTO [Department] (
      [Department_Name],
      [Department_Description],
      [Time_Created],
      [Time_Modified]
    )
    OUTPUT INSERTED.[Address_ID] INTO @Address_ID
    VALUES (
      @Department_Name_Param,
      @Department_Description_Param,
      @The_Date,
      @The_Date
    )

成為：

insert into [Address] ( Building, Factory ) values ( @Building_Param, @Factory_Param ) 
set @Address_ID = ( SELECT SCOPE_IDENTITY() )

然后，您將獲得插入的地址ID。

這是易於測試的完整代碼：

/**
 * Inserts a new entry into the department table.
 *
 * @author     Rubbel Die Katz
 */
DECLARE @The_Date DATETIME2
SET @The_Date = GETDATE()

DECLARE @Department_Name_Param NVARCHAR(MAX)
SET @Department_Name_Param = ?

DECLARE @Department_Description_Param NVARCHAR(MAX)
SET @Department_Description_Param = ?

DECLARE @Factory_Param NVARCHAR(MAX)
SET @Factory_Param = ?

DECLARE @Building_Param NVARCHAR(MAX)
SET @Building_Param = ?

DECLARE @Address_ID BIGINT
SET @Address_ID = 0



-- If the address does not exist, we will need to create it automagically.
IF NOT EXISTS (
    SELECT *
    FROM [Address]
    WHERE
      [Building] = @Building_Param
      AND [Factory] = @Factory_Param
)
  BEGIN
   insert into [Address] ( Building, Factory ) values ( @Building_Param, @Factory_Param ) 
    set @Address_ID = ( SELECT SCOPE_IDENTITY() )
  END
ELSE
-- If the address already exists, we will select its ID and store it in a variable.
    BEGIN
      SET @Address_ID =
      (
        SELECT TOP 1 [Address_ID]
        FROM [Address]
        WHERE
          [Building] = @Building_Param
          AND [Factory] = @Factory_Param
      )
    END

-- If the department does not exist, we will create it using the Address_ID provided by our previous operations.
IF NOT EXISTS (SELECT * FROM [Department] WHERE [Department_Name] = @Department_Name_Param)
BEGIN
  INSERT INTO [Department] (
    [Department_Name],
    [Department_Description],
    [Address_ID],
    [Time_Created],
    [Time_Modified]
  )
  VALUES (
    @Department_Name_Param,
    @Department_Description_Param,
    @Address_ID,
    @The_Date,
    @The_Date
  )
END

Answer 3

我對您的腳本進行了一些小的更改。 嘗試這個：

DECLARE @The_Date DATETIME2
SET @The_Date = GETDATE()

DECLARE @Department_Name_Param NVARCHAR(MAX)
SET @Department_Name_Param = ?

DECLARE @Department_Description_Param NVARCHAR(MAX)
SET @Department_Description_Param = ?

DECLARE @Factory_Param NVARCHAR(MAX)
SET @Factory_Param = ?

DECLARE @Building_Param NVARCHAR(MAX)
SET @Building_Param = ?

DECLARE @Address_ID BIGINT
SET @Address_ID = 0

-- If the address does not exist, we will need to create it automagically.
IF NOT EXISTS(
    SELECT 1
    FROM [Address]
    WHERE [Building] = @Building_Param
          AND [Factory] = @Factory_Param
)
  BEGIN
    INSERT INTO [Address]
    (
      [Factory],
      [Building],
      [Time_Created],
      [Time_Modified]
    )
    VALUES
      (
        @Factory_Param,
        @Building_Param_Param,
        @The_Date,
        @The_Date
      )
  END
--Else Part is Not Neccessary

SELECT @Address_ID = [Address_ID]
--Top 1 is not needed since the variable can hold only 1 value it will take only the Top 1 by Default
FROM [Address]
WHERE
  [Building] = @Building_Param
  AND [Factory] = @Factory_Param;

-- If the department does not exist, we will create it using the Address_ID provided by our previous operations.
IF NOT EXISTS(SELECT 1
              FROM [Department]
              WHERE [Department_Name] = @Department_Name_Param)
  BEGIN
    INSERT INTO [Department]
    (
      [Department_Name],
      [Department_Description],
      [Address_ID],
      [Time_Created],
      [Time_Modified]
    )
    VALUES
      (
        @Department_Name_Param,
        @Department_Description_Param,
        @Address_ID,
        @The_Date,
        @The_Date
      )
  END