LGTM on these changes. We will also need to have some tests for FTS - will follow up with you offline on those.

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 46.94%. Comparing base (79c9fe9) to head (fc37842).
Report is 3 commits behind head on main.

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##               main    #2167      +/-   ##
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+ Coverage     46.91%   46.94%   +0.03%     
- Complexity     4027     4036       +9     
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  Files           874      876       +2     
  Lines         52090    52128      +38     
  Branches       5468     5470       +2     
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+ Hits          24436    24472      +36     
- Misses        25906    25907       +1     
- Partials       1748     1749       +1     

Replying to previous comment inline:

• No changes are required in InformationSchemaScanner?
  • No, this is only needed in the pretty printing of the column to indicate a non-stored generated column. In INFORMATION_SCHEMA it's represented as isStored == false.
• Is the feature released in production?
  • Yes, I also confirmed by manually testing in prod.
• Also, no keyword at the end of the expression currently is defaulted to VIRTUAL ? If so, I'm trying to understand why this change is needed.
  • This change is only needed for PG, in GSQL the absence of STORED indicates non-stored. In PG, VIRTUAL indicates non-stored. So, if the STORED keyword is not specified, then the VIRTUAL keyword must be provided.