MDL-69973 xmldb: Fix problem with MariaDB >= 10.2.7 metadata defaults
authorEloy Lafuente (stronk7) <stronk7@moodle.org>
Sun, 18 Oct 2020 09:53:37 +0000 (11:53 +0200)
committerEloy Lafuente (stronk7) <stronk7@moodle.org>
Fri, 30 Oct 2020 18:27:11 +0000 (19:27 +0100)
commit533c35ff9918bdd755c70713dab8922f2b95fe8a
tree2d5a1ce80c9beca8bdf6a6a68fea35ec51a208bf
parent58ba94a7290940391d1581e591a64fc7e6bb410a
MDL-69973 xmldb: Fix problem with MariaDB >= 10.2.7 metadata defaults

With MariaDB 10.2.7 the driver was incorrectly returning '' (empty
string) as default for all the columns having null (meaning, no
default).

Also, cover the case in unit tests, it seems that we were already
testing other defaults but not the null case.
lib/dml/mysqli_native_moodle_database.php
lib/dml/tests/dml_test.php