Question

I have a CSV to convert. Transforming the data into my schema is a bit problematic.
I have a locationID in my end table, and in the CSV, there are 1’s or a NULL in about 10 columns(each one is a different location).

My logic is: If column(“locationThree”) == 1, then set locationID to 5 (for example)

I can’t figure out how to do this in SQL, is there a tool for this in Pentaho, or how could I do this in SQL?

E.G

INSERT INTO endTable(locationID)
SELECT * FROM grubbyCSVData
if(locationOne == "1")
 locationID = 5;
if(locationTwo == "1")
 locationID = 6;

Is something like that possible?

Answer 1

You might like to try combining the COALESCE and CASE expressions in SQL. Assuming you are using SQL Server something like the following might work. I have not verified that this executes correctly as I’ve just written it in the browser.

INSERT INTO endTable(locationID)
SELECT COALESCE( CASE locationOne
                 WHEN 1 THEN 5
                 ELSE NULL
                 END,
                 CASE locationTwo
                 WHEN 1 THEN 6
                 ELSE NULL
                 END
                );

Alternatively you might want to look into the PIVOT and UNPIVOT statements which are available in SQL Server 2005 onwards.