在EXECUTE/Using中使用带布尔值的PostgreSQL参数

我想在动态查询中使用参数。我有这样的陈述:

RETURN QUERY EXECUTE 'SELECT * FROM boards AS b WHERE b.slug = $1 AND $2'
USING filter_slug, parent_id_query;

ERROR: argument of AND must be type boolean, not type text

如果我这样做:

RETURN QUERY EXECUTE 'SELECT * FROM boards AS b WHERE b.slug = ''' || filter_slug || ''' AND ' || parent_id_query;

但它确实有效。

我觉得我错过了什么/不理解什么。请帮忙。