Finding and Removing Bad Characters Using Tally Tables

Kevin Feasel

2019-04-05

T-SQL

Louis Davidson shows how you can use a tally table to find and remove invalid characters from strings:

Now, the idea is that we will join the Application.People table to the Numbers table for a number of rows. We will do this for all of the numbers that are from 1 to the length of the name. Then use that value to get the substring of the value for that 1 character. I also include the Unicode value in the output to allow for some case sensitive operations, since UNICODE(‘a’) <> UNICODE(‘A’).

This is an example of how powerful tally tables can be.

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