In recent years, researches focus on addressing the query bottleneck issue using semantic cache. However, the challenges of this method are how to increase cache hit ratio, decrease the query processing time, and address cache consistency issue. In this paper, we construct segment access-aware dynamic semantic cache for relational databases. Some definitions of semantic segment, probe query, and remainder query are proposed to describe the semantic cache. Then, estimation of the query result is proposed. Next, cache access algorithm of our proposed segment access-aware dynamic semantic cache is presented in case of cache exact hit, cache extended hit, cache partial hit and cache miss. Cache item with effective lifecycle tag is proposed to address cache consistency issue. Finally, experimental results show that this approach performs better than regular semantic cache and decisional semantic cache.