Select Data from Top N Columns



Suppose you have table with many columns and often you need data from first 15 or 20 columns. You have to specify all the columns in your select statement. This procedure will select top N columns you want. All you have to do is to supply table name and number of columns you want

Here is the procedure


CREATE procedure TopNcolumns (@tableName varchar(100),@n int) 
as   
Declare @s varchar(2000)   
set @s='' 
If @n>=0  
Begin 
set rowcount @n 
Select @s=@s+','+ column_name from information_schema.columns  
where table_name=@tablename order by ordinal_position 
Set rowcount 0 
Set @s=substring(@s,2,len(@s)-1) 
Exec('Select '+@s+' from '+@tablename
End 
else 
Select 'Negative values are not allowed' as Error 

 

If you execute TopNColumns 'Mytable',12  then first 12 columns with data from the table Mytable will be displayed



Published 27 August 2007 16:23 by Madhivanan
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