Question

I create temp tables quite often in SQL and I am looking into a way to generate the column names and datatypes automatically for the table definition so I don’t have to look them all up everytime.

For example I run:

SELECT CustomerID
  ClientID,
  FirstName
  LastName
INTO #Test
From dbo.Customer

To initially setup the temp table with the appropriate columns and data I need. Once I get that all done, I then go back in and take out the INTO statement and write the following:

CREATE TABLE #Test
(
...
...
);

I want to find a way to auto generate the column names and datatypes from the initial creation of the temp table. Right now, since I am initially inserting into an automatically created temp table, I use this:

EXEC tempdb..sp_help '#Test';

This gives me everything I need without having to look all the column datatypes up, but I wanted to know if there was a way to just auto gen the column names off of something like this. So the auto gen would generate:

CustomerID int,
ClientID int,
FirstName varchar(50),
LastName varchar(50)

This would allow me to just copy and paste this into my create table statement.

Answer 1

this might give you a start:

DECLARE @viewname VARCHAR(50);
SET @viewname ='tableorviewname';
SELECT  c.name + ' '+ t.name + 
case t.name  
WHEN 'varchar' THEN '('+CAST(c.max_length AS VARCHAR(3) )+'),'
ELSE ',' 
end
FROM sys.columns c
INNER JOIN sys.types AS t ON c.system_type_id = t.system_type_id
WHERE object_id = (SELECT object_id from sys.objects where name = @viewname)
ORDER BY c.column_id

EDIT: TEMP TABLES:

temp tables are slightly different, for instance this works in sql 2008 for a temp table named #tv_source

DECLARE @viewortablename VARCHAR(50);
SET @viewortablename ='tempdb..#tv_source';
SELECT  c.name + ' '+ t.name + 
case t.name  
WHEN 'varchar' THEN '('+CAST(c.max_length AS VARCHAR(3) )+'),'
ELSE ',' 
end
FROM tempdb.sys.columns c
INNER JOIN sys.types AS t ON c.system_type_id = t.system_type_id
WHERE object_id =  object_id(@viewortablename)
ORDER BY c.column_id

NOTES: this gives a comma separated list, but did NOT attempt to remove that last comma, it gives only a list, which you would likely want to put on a string and manipulate, etc. then use as a dynamic sql or somthing. Still, it should give you a start on what you wish to do.

NOTE for to others, sql 2000 would not display the lengths properly for instance on a varchar(45), it would just list the varchar part and I did not attempt to rework that for this question.