Fixed #18770 export of DEFAULT value of MySQL tables is wrong in db_schema.dba

[jdespatis]

Fix of issues.ez.no/IssueView.php?Id=18770 (heavy explanations in this issue)

[andrerom]

Looks ok on first glimpse, but are there any unit tests covering this code or are we driving with blind folds here? :)

[jdespatis]

You mean automatic unit test ? if there's a way to do so, I can do it.

If not, I can propose you this:
1/ I create a table A will all cases possible (not null/null) (get a mysql1.sql to create A)
2/ create the db_schema.dba from that table
3/ then drop A, and recreate it from db_schema.dba, then dump again a mysql2.sql
4/ and then compare both mysql1.sql and mysql2.sql to see if we're in sync

That's indeed the process I've followed for my multiple tests

Tell me

[nfrp]

Thanks @jdespatis for this contribution !

@andrerom : is the proposed manual testing process satisfactory ? Is there an automated unit-testing way of proceeding here ?

@gggeek : is Jérôme's second, minimalistic patch (proposed here : http://issues.ez.no/18770 ) a less intrusive, more easily mergeable approach ?

[jdespatis]

To be more precise, the mysql.sql to create should handle all null/not null, with/without default, for each type supported by mysql, in order to have a complete overall test
and then perform the sql => dba => sql to see if we get the same thing

Of course, this logic of having a test .sql would be nice to have also for other dbs (with all their specific types handled), maybe you have those sql to launch a unit test. If yes, do not hesitate to tell me where it's in the code tree, so that I can add other types or cases I encounter