def as_sql(self, with_limits=True, with_col_aliases=False, subquery=False):
        """ Patching final SQL query."""
        query = self.query
        try:
            where_sql, where_params = query.where.as_sql(self, self.connection)
        except EmptyResultSet:
            # Where node compiled to always-false condition, but we still need
            # to call pre_sql_setup() and other methods by super().as_sql
            pass
        else:
            # creating WHERE node with sphinx-aware node implementation if
            # everything is fine
            where = sqls.SphinxWhereNode()
            # Adding MATCH() node to WHERE node if needed
            self._add_match_extra(query, where)
            query.where = where
            # Adding where conditions to SELECT clause because of better
            # support of SQL expressions in sphinxsearch.
            self._add_where_result(query, where_sql, where_params)

        sql, args = super().as_sql(with_limits, with_col_aliases)

        # empty SQL doesn't need patching
        if (sql, args) == ('', ()):
            return sql, args

        # removing unsupported by sphinxsearch OFFSET clause
        # replacing it with LIMIT <offset>, <limit>
        sql = re.sub(r'LIMIT (\d+) OFFSET (\d+)$', 'LIMIT \\2, \\1', sql)

        # patching GROUP BY clause
        group_limit = getattr(query, 'group_limit', '')
        group_by_ordering = self.get_group_ordering()
        if group_limit:
            # add GROUP <N> BY expression
            group_by = 'GROUP %s BY \\1' % group_limit
        else:
            group_by = 'GROUP BY \\1'
        if group_by_ordering:
            # add WITHIN GROUP ORDER BY expression
            group_by += group_by_ordering
        sql = re.sub(r'GROUP BY ((\w+)(, \w+)*)', group_by, sql)

        # adding sphinxsearch OPTION clause
        options = getattr(query, 'options', None)
        if options:
            keys = sorted(options.keys())
            values = [options[k] for k in keys if k not in self.safe_options]

            opts = []
            for k in keys:
                if k in self.safe_options:
                    opts.append("%s=%s" % (k, options[k]))
                else:
                    opts.append("%s=%%s" % k)
            sql += ' OPTION %s' % ', '.join(opts) or ''
            args += tuple(values)
        return sql, args
    def as_sql(self, with_limits=True, with_col_aliases=False, subquery=False):
        """ Patching final SQL query."""
        where, self.query.where = self.query.where, sqls.SphinxWhereNode()
        match = getattr(self.query, 'match', None)
        if match:
            # add match extra where
            self._add_match_extra(match)

        connection = self.connection

        where_sql, where_params = where.as_sql(self, connection)
        # moving where conditions to SELECT clause because of better support
        # of SQL expressions in sphinxsearch.

        if where_sql:
            # Without annotation queryset.count() receives 1 as where_result
            # and count it as aggregation result.
            self.query.add_annotation(
                sqls.SphinxWhereExpression(where_sql, where_params),
                '__where_result')
            # almost all where conditions are now in SELECT clause, so
            # WHERE should contain only test against that conditions are true
            self.query.add_extra(None, None, ['__where_result = %s'], (True, ),
                                 None, None)

        sql, args = super().as_sql(with_limits, with_col_aliases)

        # empty SQL doesn't need patching
        if (sql, args) == ('', ()):
            return sql, args

        # removing unsupported by sphinxsearch OFFSET clause
        # replacing it with LIMIT <offset>, <limit>
        sql = re.sub(r'LIMIT (\d+) OFFSET (\d+)$', 'LIMIT \\2, \\1', sql)

        # patching GROUP BY clause
        group_limit = getattr(self.query, 'group_limit', '')
        group_by_ordering = self.get_group_ordering()
        if group_limit:
            # add GROUP <N> BY expression
            group_by = 'GROUP %s BY \\1' % group_limit
        else:
            group_by = 'GROUP BY \\1'
        if group_by_ordering:
            # add WITHIN GROUP ORDER BY expression
            group_by += group_by_ordering
        sql = re.sub(r'GROUP BY ((\w+)(, \w+)*)', group_by, sql)

        # adding sphinxsearch OPTION clause
        options = getattr(self.query, 'options', None)
        if options:
            keys = sorted(options.keys())
            values = [options[k] for k in keys if k not in self.safe_options]

            opts = []
            for k in keys:
                if k in self.safe_options:
                    opts.append("%s=%s" % (k, options[k]))
                else:
                    opts.append("%s=%%s" % k)
            sql += ' OPTION %s' % ', '.join(opts) or ''
            args += tuple(values)
        return sql, args