Bug 20229: Explicitly list the SQL modes we support

In our installation procedure we ask the administrator to edit the
MySQL|MariaDB configuration file to specify the SQL modes we support
(see bug 17258 comment 6 and 7 for more information).

We are on the way to catch and fix all these issues and support these
stricter modes (as they highlight problem in our codebase/DB structure)
but in the meanwhile it may be good to remove this step and revert the
changes when we are ready.

TODO:
- Remove that for dev installations (to let developers catch these bugs)
- Edit the wiki page to remove this step

Test plan:
0. Do not apply this patch
1. Edit your MySQL|MariaDB config and add:
sql-mode = "ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
to the [mysqld] section (or edit it)
2. Restart your DBMS
3. Try to make the app explode (watch the logs)
(tips: you should get "'koha_kohadev.me.id' isn't in GROUP BY" when
editing an order)
4. Apply the patch, restart_all, restart your DBMS
5. Try to recreate the failure
=> You should no longer see the error in the logs

Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>

Koha/Database.pm

@@ -69,12 +69,13 @@ sub _new_schema {
 
 
 
-    my ( %encoding_attr, $encoding_query, $tz_query );
+    my ( %encoding_attr, $encoding_query, $tz_query, $sql_mode_query );
     my $tz = $ENV{TZ};
     if ( $db_driver eq 'mysql' ) {
         %encoding_attr = ( mysql_enable_utf8 => 1 );
         $encoding_query = "set NAMES 'utf8'";
         $tz_query = qq(SET time_zone = "$tz") if $tz;
+        $sql_mode_query = q{SET sql_mode = 'IGNORE_SPACE,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION'};
     }
     elsif ( $db_driver eq 'Pg' ) {
         $encoding_query = "set client_encoding = 'UTF8';";
@@ -93,6 +94,7 @@ sub _new_schema {
             on_connect_do => [
                 $encoding_query || (),
                 $tz_query || (),
+                $sql_mode_query || (),
             ]
         }
     );