Question

I have a table with over 400 columns, and these are named with our vendor’s archaic naming system. I need to move this data into a new table which uses our company’s naming conventions, so I have to change the names of these 400 columns.

Fortunately, I also have a table that cross-references the current column names with what they should become, like so:

Acronym  | Name
----------------
A        | ColumnNameA
B        | ColumnNameB
C        | ColumnNameC

etc…

So my question is this:
If it were only a few rows, I could easily do

SELECT 
   A AS ColumnNameA, 
   B AS ColumnNameB 
FROM 
   Table

But there are just too many columns to do this by hand. What’s the best way to dynamically change column names in a SELECT statement based off of a cross-ref table?

My effort so far:

I was thinking something along the lines of

SET @sqlCommand = 'SELECT ' + @columns + ' FROM Table'
EXEC (@sqlCommand)

but I have no idea how to set @columns to be a dynamically generated list of all the acronyms as the final column names. Is this even a viable approach?

Answer 1

DECLARE @sql NVARCHAR(MAX) = N'';

SELECT @sql += ',' + QUOTENAME(Acronym) + ' AS ' + QUOTENAME(Name)
FROM dbo.AcronymTable;

SET @sql = 'SELECT ' + STUFF(@sql, 1, 1, N'') + ' FROM dbo.Table;';

PRINT @sql;
--EXEC sp_executesql @sql;