return $self->SUPER::_where_field_BETWEEN ($lhs, $op, $rhs);
}
-
-
-# DB2 is the only remaining DB using this. Even though we are not sure if
-# RowNumberOver is still needed here (should be part of SQLA) leave the
-# code in place
+# Slow but ANSI standard Limit/Offset support. DB2 uses this
sub _RowNumberOver {
my ($self, $sql, $order, $rows, $offset ) = @_;
return $sql;
}
+# Crappy Top based Limit/Offset support. MSSQL uses this currently,
+# but may have to switch to RowNumberOver one day
+sub _Top {
+ my ( $self, $sql, $order, $rows, $offset ) = @_;
+
+ croak '$order supplied to SQLAHacks limit emulators must be a hash'
+ if (ref $order ne 'HASH');
+
+ $order = { %$order }; #copy
+
+ my $last = $rows + $offset;
+
+ my $req_order = $self->_order_by ($order->{order_by});
+ my $limit_order = $req_order ? $order->{order_by} : $order->{_virtual_order_by};
+
+ delete $order->{$_} for qw/order_by _virtual_order_by/;
+ my $grpby_having = $self->_order_by ($order);
+
+ my ( $order_by_inner, $order_by_outer ) = $self->_order_directions($limit_order);
+
+ $sql =~ s/^\s*(SELECT|select)//;
+
+ $sql = <<"SQL";
+ SELECT * FROM
+ (
+ SELECT TOP $rows * FROM
+ (
+ SELECT TOP $last $sql $grpby_having $order_by_inner
+ ) AS foo
+ $order_by_outer
+ ) AS bar
+ $req_order
+
+SQL
+ return $sql;
+}
+
+
# While we're at it, this should make LIMIT queries more efficient,
# without digging into things too deeply
my $ret = '';
my @extra;
if (ref $_[0] eq 'HASH') {
+
if (defined $_[0]->{group_by}) {
$ret = $self->_sqlcase(' group by ')
.$self->_recurse_fields($_[0]->{group_by}, { no_rownum_hack => 1 });
}
+
if (defined $_[0]->{having}) {
my $frag;
($frag, @extra) = $self->_recurse_where($_[0]->{having});
push(@{$self->{having_bind}}, @extra);
$ret .= $self->_sqlcase(' having ').$frag;
}
+
if (defined $_[0]->{order_by}) {
$ret .= $self->_order_by($_[0]->{order_by});
}
+
if (grep { $_ =~ /^-(desc|asc)/i } keys %{$_[0]}) {
return $self->SUPER::_order_by($_[0]);
}
+
} elsif (ref $_[0] eq 'SCALAR') {
$ret = $self->_sqlcase(' order by ').${ $_[0] };
} elsif (ref $_[0] eq 'ARRAY' && @{$_[0]}) {
- my @order = @{+shift};
- $ret = $self->_sqlcase(' order by ')
- .join(', ', map {
- my $r = $self->_order_by($_, @_);
- $r =~ s/^ ?ORDER BY //i;
- $r;
- } @order);
+ my @order = map {
+ my $r = $self->_order_by($_, @_);
+ $r =~ s/^ ?ORDER BY //i;
+ $r || ();
+ } @{+shift};
+
+ $ret = $self->_sqlcase(' order by ') . join(', ', @order) if @order;
+
} else {
$ret = $self->SUPER::_order_by(@_);
}
sub _resolve_order {
my ($self, $order) = @_;
- $order = $order->{order_by} if (ref $order eq 'HASH' and $order->{order_by});
if (ref $order eq 'HASH') {
$order = [$self->_resolve_order_hash($order)];
croak "$key is not a valid direction, use -asc or -desc";
}
}
+
return @new_order;
}