PostgreSQL/SQLite: Sympa tries creating temporary views in databases unnecessarily (#1812)

src/lib/Sympa/DatabaseDriver/PostgreSQL.pm

@@ -61,18 +61,11 @@ sub connect {
 
     # - Configure Postgres to use ISO format dates.
     # - Set client encoding to UTF8.
-    # - Create a temporary view "dual" for portable SQL statements.
     # Note: utf8 flagging must be disabled so that we will consistently use
     #   UTF-8 bytestring as internal format.
-    # Note: PostgreSQL <= 8.0.x didn't support temporary view but >= 7.3.x
-    #   supported CREATE OR REPLACE statement.
     $self->__dbh->{pg_enable_utf8} = 0;    # For DBD::Pg 3.x
     $self->__dbh->do("SET DATESTYLE TO 'ISO';");
     $self->__dbh->do("SET NAMES 'utf8'");
-    defined $self->__dbh->do(
-        q{CREATE TEMPORARY VIEW dual AS SELECT 'X'::varchar(1) AS dummy;})
-        or $self->__dbh->do(
-        q{CREATE OR REPLACE VIEW dual AS SELECT 'X'::varchar(1) AS dummy;});
 
     return 1;
 }

src/lib/Sympa/DatabaseDriver/SQLite.pm

@@ -63,8 +63,6 @@ sub connect {
     } else {
         $self->__dbh->func(5000, 'busy_timeout');
     }
-    # Create a temoprarhy view "dual" for portable SQL statements.
-    $self->__dbh->do(q{CREATE TEMPORARY VIEW dual AS SELECT 'X' AS dummy;});
 
     # Create a function MD5().
     $self->__dbh->func(

src/lib/Sympa/DatabaseManager.pm

@@ -55,6 +55,21 @@ sub instance {
         unless $self = Sympa::Database->new($db_conf->{'db_type'}, %$db_conf)
         and $self->connect;
 
+    # Compatibility concern.
+    # - Create a temporary view "dual" for portable SQL statements.
+    if (ref $self eq 'Sympa::DatabaseDriver::PostgreSQL') {
+        # Note: PostgreSQL <= 8.0.x didn't support temporary view but >= 7.3.x
+        #   supported CREATE OR REPLACE statement.
+        defined $self->__dbh->do(
+            q{CREATE TEMPORARY VIEW dual AS SELECT 'X'::varchar(1) AS dummy;})
+            or $self->__dbh->do(
+            q{CREATE OR REPLACE VIEW dual AS SELECT 'X'::varchar(1) AS dummy;}
+            );
+    } elsif (ref $self eq 'Sympa::DatabaseDriver::SQLite') {
+        $self->__dbh->do(
+            q{CREATE TEMPORARY VIEW dual AS SELECT 'X' AS dummy;});
+    }
+
     # At once connection succeeded, we keep trying to connect.
     # Unless in a web context, because we can't afford long response time on
     # the web interface.

t/Database_SQLite.t

@@ -78,5 +78,10 @@ if (3035005 <= $DBD::SQLite::sqlite_version_number) {
         qr/not support/, 'delete_field(unsupported)';
 }
 
+my $sth = $sdm->do_prepared_query(q{SELECT '', 0, NULL FROM dual});
+my $rows = $sth->fetchall_arrayref if $sth;
+is_deeply $rows, [['', 0, undef]], 'temporary view "dual" exists';
+$sth->finish;
+
 done_testing();