Do you think we should check if value provided as default is a valid json ? json_validate seems free to use as Tempest require 8.3+

Yes, that makes sense!

Latest versions of MySQL accept default value for json but this require a version check.
I didn't want to add this complexity (at least for this pr) as this was not done either for text type before

Yeah we can ignore this for now :)

We should also make sure that JSON columns are eventually mapped to array properties. But that's outside the scope of this PR.

json_validate added :)
I'm not sure about the Exception name and the new test, let me know if this is suitable

Thanks!

Pull Request Test Coverage Report for Build 11756751614

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Details

• 31 of 31 (100.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.06%) to 82.508%

Totals
Change from base Build 11760861421:	0.06%
Covered Lines:	7283
Relevant Lines:	8827

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