MQT, an Approach for Run-Time Query Translation: From EOL to SQL.
Xabier De Carlos, Goiuria Sagardui, Salvador Trujillo · 2014
Abstract. Managing models requires extracting information from them and modifying them, and this is performed through queries. Queries can be executed at the model or at the persistence-level. Both are comple-mentary but while model-level queries are closer to modelling engineers, persistence-level queries are specific to the persistence technology and leverage its capabilities. This paper presents MQT, an approach that translates EOL (model-level queries) to SQL (persistence-level queries) at runtime. Runtime translation provides several benefits: (i) queries are executed only when the information is required; (ii) context and meta-model information is used to get more performant translated queries; and (iii) supports translating query programs using variables and depen-dant queries. Translation process used by MQT is described through two examples and we also evaluate performance of the approach.