SQLite: Adding a UDF concat_ws().

It is supported by MySQL, PostgreSQL and Oracle (also MS SQL 2017) while SQLite does not.

Author: ikedas

src/lib/Sympa/DatabaseDriver/SQLite.pm

@@ -64,6 +64,14 @@ sub connect {
         $self->__dbh->func(5000, 'busy_timeout');
     }
 
+    # Compatibility with other drivers.
+    # concat_ws(): Since 6.2.XX.
+    $self->__dbh->func('concat_ws', -1, sub {
+            my $sep = shift;
+            return undef unless defined $sep;
+            return join $sep, grep {defined} @_;
+        }, 'create_function');
+
     return 1;
 }