本内容共分上下两篇建议从上篇开始看,下篇衔接上篇
在数据库设计中,命名规范、合适的字段类型、主键设计、字段长度、逻辑删除、通用字段和表的字段数量都是非常重要的考虑因素。
除了 MySQL 本身之外,如何分析定位其他因素的可能性?
问题:mybatisplus+mysql执行sql查询时报以下错误:line 1:43 no viable alternative at input
长达 1.7 万字的 explain 关键字指南!
Lost connection to MySQL server…
[ERROR] InnoDB: Expected to open 3 undo tablespaces but was able to find only 0 undo tablespaces. Set the innodb_undo_tablespaces parameter to the correct value and retry. Suggested value is 0
ERROR 1418 (HY000): This function has none of DETERMINISTIC, NO SQL, or READS SQL DATA in its declaration and binary logging is enabled (you *might* want to use the less safe log_bin_trust_function_creators variable)
Error Code: 1175. You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column.
Error 1390 (HY000): Prepared statement contains too many placeholders