Best way to flatten/denormalize SQL lookup tables?

Question

I have a bunch of tables like this:

Lookup_HealthCheckupRisks
------------
ID  Name
1   Anemia
2   Anorexic
3   Bulemic
4   Depression
...
122   Syphilis



Pati         


        

Answer 1

What you need is called a crosstab query.

If you're using Microsoft SQL Server, you can use the PIVOT operator to do it.

Other brands of RDBMS have varying support for this type of query. Worst case is you'll have to use dynamic SQL to hard-code very value from the lookup table into a join to your main table. This is not practical when you have 122 distinct values.

Also see SO questions tagged pivot or crosstab.