SQL-Statement with dynamic table-names or redesign?

Question

I have a MS SQL 2008 database which stores data for creating a weighted, undirected graph. The data is stored in tables with the following structure:

[id1] [int]         


        

Answer 1

Maybe I did not understand everything, but:

CREATE PROCEDURE dbo.GetMyData (
     @TableName AS varchar(50)
    )
AS 
BEGIN
    IF @TableName = 'Table_1' 
        BEGIN
            SELECT  id1
                   ,id2
                   ,[weight]
            FROM    dbo.Table_1
        END

    IF @TableName = 'Table_2' 
        BEGIN
            SELECT  id1
                   ,id2
                   ,[weight]
            FROM    dbo.Table_2
        END
END 

and then:

EXEC dbo.GetMyData @TableName = 'Table_1' 

A different technique involves using synonyms dynamically, for example:

DECLARE @TableName varchar(50)
SET @TableName = 'Table_1' 

-- drop synonym if it exists
IF object_id('dbo.MyCurrentTable', 'SN') IS NOT NULL 
    DROP SYNONYM MyCurrentTable ;

-- create synonym for the current table
IF @TableName = 'Table_1' 
    CREATE SYNONYM dbo.MyCurrentTable FOR dbo.Table_1 ;

IF @TableName = 'Table_2' 
    CREATE SYNONYM dbo.MyCurrentTable FOR dbo.Table_2 ;

-- use synonym
SELECT  id1, id2, [weight] 
FROM dbo.MyCurrentTable