详解mysql-explain 三月 31, 2019 发布在 数据层 | 大约4484字 | 预计9分钟读完 | 优化 explain结果解读 id select_type simple primary union dependent union subquery dependent subquery derived table type system const eq_ref ref ref_or_null unique_subquery index_subquery range index all possible_keys key key_len ref rows extra distinct not exists using filesort using index using temporary using where explain范例分析 阅读全文