@dblackwe
I can suggest another way. If you are finding it difficult to get your filter SQL with REGEXP then just don't have a regexp in filter SQL at all. Have it as a plain parameter like
WHERE column LIKE '%${varible}'
So now your filter has a parameter, $variable
In workflow User-Input, you can define your Regex for this string $varibale. So this will give you the desired result.
sinhaa
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