如何在使用光標的不同數據庫中創建過程

Question

所以我試圖在不同的數據庫中創建過程。我不應該知道數據庫的名稱。我試圖製作嵌套遊標，第一個是以動態方式獲取數據庫的名稱，另一個是創建/更改過程;我用EXISTS來創建一個程序，而不是用EXISTS來修改它們。但不知何故數據庫堅持'主'，它永遠不會循環其他的。我知道我的內嵌套光標有問題，但我不知道這是什麼。 這裏是我的編碼：

DECLARE GetDatabases CURSOR 
FOR 
    SELECT name 
    FROM sys.databases 
OPEN GetDatabases 
DECLARE @DBName NVARCHAR(100) 
DECLARE @cmd NVARCHAR(Max) 

FETCH NEXT 
FROM GetDatabases 
INTO @DBName 

WHILE @@FETCH_STATUS = 0 
BEGIN 
    set @cmd='use ' + @DBName 
    print @cmd 
    exec sp_executesql @cmd 
    FETCH NEXT 
    FROM GetDatabases 
    INTO @DBName 
     DECLARE AutoProc CURSOR 
     FOR 
      SELECT TABLE_SCHEMA,TABLE_NAME 
      FROM INFORMATION_SCHEMA.TABLES 
      WHERE TABLE_TYPE='BASE TABLE' 
     OPEN AutoProc 
     DECLARE @TableName NVARCHAR(100) 
     DECLARE @TableSchema NVARCHAR(100) 

     FETCH NEXT 
     FROM AutoProc 
     INTO @TableSchema,@TableName 

     WHILE @@FETCH_STATUS = 0 
     BEGIN 
     IF EXISTS(SELECT * FROM sys.objects WHERE type = 'P' AND OBJECT_ID = OBJECT_ID('@TableName')) 
      exec('ALTER PROCEDURE USP_SELECT_'+@TableName+' AS 
      BEGIN 
      SELECT * 
      FROM '+@TableSchema+'.'+@TableName+' 
      END ;') 
     IF NOT EXISTS (SELECT * FROM sys.objects WHERE type = 'P' AND OBJECT_ID = OBJECT_ID('@TableName')) 
      exec('CREATE PROCEDURE USP_SELECT_'+@TableName+' AS 
      BEGIN 
      SELECT * 
      FROM '+@TableSchema+'.'+@TableName+' 
      END ;') 
      FETCH NEXT 
      FROM AutoProc 
      INTO @TableSchema,@TableName 
     END 
     CLOSE AutoProc 
     DEALLOCATE AutoProc 
END 
CLOSE GetDatabases 
DEALLOCATE GetDatabases 

PS：我不應該知道數據庫的名字，因爲我想寫一個「常規」的程序，以便它可以適用於所有的SQL服務器用戶數據庫，不只是我的。 P.S2：我使用了嵌套遊標，但由於它們的災難性表現，我會很欣賞其他方式！

乾杯！

Answer 1

而不是使用遊標，嘗試使用while語句，並遍歷一個臨時變量表​​。

DECLARE @Databases TABLE 
(
    ID int IDENTITY(1,1), 
    DatabaseName varchar(100) 
) 


INSERT INTO @Databases 
SELECT name FROM sys.databases 

DECLARE @Idx int = (select count(*) from @Databases) 

WHILE(@Idx > 0) 
    BEGIN 

    DECLARE @CurrentDatabase varchar(100) = (select DatabaseName from @Databases where @Idx = ID) 

    DECLARE @SchemaData TABLE 
    (
    ID int IDENTITY(1,1), 
    Table_Schema varchar(20), 
    Table_Name varchar(255) 
    ) 

    DECLARE @Sql varchar(max) = 'SELECT [TABLE_SCHEMA],[TABLE_NAME] FROM [' + @CurrentDatabase + '].[INFORMATION_SCHEMA].[TABLES]'  

    INSERT INTO @SchemaData 
     EXEC (@Sql) 

    DECLARE @SchemaIdx int = (select count(*) from @SchemaData) 

    WHILE(@SchemaIdx > 0) 
     BEGIN 

     DECLARE @CurrentSchema varchar(20), @CurrentTable varchar(255) 

     SELECT @CurrentSchema = Table_Schema, @CurrentTable = Table_Name from  @SchemaData where ID = @SchemaIdx 

     DECLARE @Sql2 varchar(max) = 
      'IF EXISTS(SELECT * FROM sys.objects WHERE type = ''P'' AND OBJECT_ID = OBJECT_ID(' + @CurrentTable + ')) 
      exec(''ALTER PROCEDURE USP_SELECT_'+ @CurrentTable + ' AS 
      BEGIN 
      SELECT * 
      FROM '+ @CurrentSchema + '.'+ @CurrentTable + ' 
      END ;'')' 

     PRINT @Sql2 

     SET @SchemaIdx = @SchemaIdx - 1; 
    END 



    SET @Idx = @Idx - 1; 
END