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Question

此代码涉及递归存储过程调用和避免游标名称冲突的“不太好”的方法。最后我不在乎它是否使用游标。只是在寻找最优雅的方法。我主要将它用作跟踪存储过程层次结构的简单方法(无需购买产品)。我在“动态 sql”中尝试了游标，但运气不佳。我想深入 10 个级别。

期望的输出:

sp_Master_Proc_Name  -- sp_Child_Proc_1_Name  ---- sp_Sub_Proc_1_Name    -- sp_Child_Proc_2_Name  -- sp_Child_Proc_3_Name

Its not pretty, but here is the code (and it didn't work as expected)

    CREATE PROCEDURE SP_GET_DEPENDENCIES
    (
      @obj_name varchar(300),
      @level int
    )
    AS
    DECLARE @sub_obj_name varchar(300)
    IF @level = 1
      BEGIN
        PRINT @obj_name
      END

    IF @level = 1
      BEGIN 
        DECLARE the_cursor_1 CURSOR FOR 
            SELECT DISTINCT REPLICATE('--', @level) + ' ' + c.name FROM dbo.sysdepends a
              INNER JOIN dbo.sysobjects b ON a.id = b.id
              INNER JOIN dbo.sysobjects c ON a.depid = c.id
              WHERE b.name = @obj_name
        OPEN the_cursor_1
        SET @level = @level + 1
        FETCH NEXT FROM the_cursor_1 INTO @sub_obj_name 
        WHILE @@FETCH_STATUS = 0 
          BEGIN 
            PRINT @sub_obj_name
            EXEC SP_GET_DEPENDENCIES @sub_obj_name, @level 
            FETCH NEXT FROM the_cursor_1 INTO @sub_obj_name 
          END
        CLOSE the_cursor_1
        DEALLOCATE the_cursor_1
      END

    IF @level = 2
      BEGIN 
        DECLARE the_cursor_2 CURSOR FOR 
            SELECT DISTINCT REPLICATE('--', @level) + ' ' + c.name FROM dbo.sysdepends a
              INNER JOIN dbo.sysobjects b ON a.id = b.id
              INNER JOIN dbo.sysobjects c ON a.depid = c.id
              WHERE b.name = @obj_name
        OPEN the_cursor_2
        SET @level = @level + 1
        FETCH NEXT FROM the_cursor_2 INTO @sub_obj_name 
        WHILE @@FETCH_STATUS = 0 
          BEGIN 
            PRINT @sub_obj_name
            EXEC SP_GET_DEPENDENCIES @sub_obj_name, @level 
            FETCH NEXT FROM the_cursor_2 INTO @sub_obj_name 
          END
        CLOSE the_cursor_2
        DEALLOCATE the_cursor_2
      END

    IF @level = 3
      BEGIN 
        DECLARE the_cursor_3 CURSOR FOR 
            SELECT DISTINCT REPLICATE('--', @level) + ' ' + c.name FROM dbo.sysdepends a
              INNER JOIN dbo.sysobjects b ON a.id = b.id
              INNER JOIN dbo.sysobjects c ON a.depid = c.id
              WHERE b.name = @obj_name
        OPEN the_cursor_3
        SET @level = @level + 1
        FETCH NEXT FROM the_cursor_3 INTO @sub_obj_name 
        WHILE @@FETCH_STATUS = 0 
          BEGIN 
            PRINT @sub_obj_name
            EXEC SP_GET_DEPENDENCIES @sub_obj_name, @level 
            FETCH NEXT FROM the_cursor_3 INTO @sub_obj_name 
          END
        CLOSE the_cursor_3
        DEALLOCATE the_cursor_3
      END

Answer 1

对于 ms sql server，您可以使用 CURSOR LOCAL，然后游标在存储过程调用中是本地的，您的代码变得更加简单:

CREATE PROCEDURE uspPrintDependencies
(
    @obj_name varchar(300),
    @level int
)
AS
SET NOCOUNT ON
DECLARE @sub_obj_name varchar(300)

if @level > 0 begin
    PRINT Replicate(' ',@level) + @obj_name
end
else begin
    PRINT @obj_name
end

DECLARE myCursor CURSOR LOCAL FOR 
    SELECT 
        DISTINCT c.name 
    FROM dbo.sysdepends a
        INNER JOIN dbo.sysobjects b ON a.id = b.id
        INNER JOIN dbo.sysobjects c ON a.depid = c.id
    WHERE b.name = @obj_name
OPEN myCursor
SET @level = @level + 1
FETCH NEXT FROM myCursor INTO @sub_obj_name 
WHILE @@FETCH_STATUS = 0 BEGIN 
    EXEC uspPrintDependencies @sub_obj_name, @level 
    FETCH NEXT FROM myCursor INTO @sub_obj_name 
END
CLOSE myCursor
DEALLOCATE myCursor
GO