Problem solve Get help with specific problems with your technologies, process and projects.

Normalizing a comma-delimited list

I have a table with data as below. How to write an SQL statement to get this result?

I've a table with data as below:

Key CustNo
 1   0431,0324,98731
 2   12,32,45,56,67,878

How to write an SQL statement to get the result as:

1 0431
1 0324
1 98731
2 12
2 32
2 45

... and so on?

Short answer: don't do this in SQL.

Longer answer: you can do this with SQL, but the SQL is very complex and ugly. There is a semi-easy way to do it, provided there happens to exist a Customers table which has individual CustNo values as primary (or at least unique) key.

select m.Key
     , c.CustNo
  from myTable as m
  join Customers as c
    on  ',' || m.CustNo || ','
  like '%,' || c.CustNo || ',%'

While this works, it's not very efficient. You should consider normalizing your table.

This was last published in January 2007

Dig Deeper on Oracle and SQL

Have a question for an expert?

Please add a title for your question

Get answers from a TechTarget expert on whatever's puzzling you.

You will be able to add details on the next page.

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.