It could be hard for businesspeople to perform complex conditional queries and multi-table join queries on pseudo tables in SPL because they need to know pseudo table structure and table join relationship and master SPL fundamentals. DQL offers a Semantic layer for building models conveniently and flexibly, through which you can use the clear and concise DQL syntax instead of the more complicated SPL syntax. And you can perform data queries using user-friendly statements based on simple and easy to understand data structure.