Add LEFT, RIGHT and SUBSTRING SQL functions

[aydun]

Overview

Add LEFT, RIGHT and SUBSTRING SQL functions to APIv4

Before

no sense of direction

After

improved

Technical Details

LEFT() and RIGHT() are not strictly needed since the same results can be achieved with SUBSTRING(), but they are more intuitive and user-friendly. And SQL provides them all.

@colemanw : LEFT & RIGHT don't work well with '0' characters, but that is the default shown. Can we set a default value for the parameter?

Comments

[civibot]

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[demeritcowboy]

Would SUBSTRING() be more general? You can do negative numbers with it to get the same as RIGHT.

[aydun]

Would SUBSTRING() be more general? You can do negative numbers with it to get the same as RIGHT.

@demeritcowboy SUBSTRING() is more general but less intuitive and user-friendly. So let's do both...

[demeritcowboy]

Ok sounds good.
And I agree that the default of 0 that appears would be nice to change.
And maybe out of scope since it's a general issue but for "Extract text" there's no labels on the parameters so it's not clear what it wants.

Also out of scope but unless I'm missing how to group-by on a transformed field this won't help the original stackexchange question. But the feature is still useful for other reasons.

[colemanw]

Thanks for this @aydun. It would be helpful to add these to the test suite, can just add a few lines to the existing SqlFunctionTest.

This doesn't solve your UX default issue but I noticed a bug when handling 0 as an argument & pushed a fix: #26553

[aydun]

@colemanw - thanks, test added.