乘风的博客

转载，原文地址：http://panyi5202.iteye.com/blog/6124141.对查询进行优化，应尽量避免全表扫描，首先应考虑在 where 及 order by 涉及的列上建立索引。 2.应尽量避免在 where 子句中对字段进行 null 值判断，否则将导致引擎放弃使用索引而进行全表扫描，如： select id from t where num is nu

org.bson.codecs.configuration.CodecConfigurationException: Can't find a codec for class java.util.ArrayList.

MongoDB 连接查询 $lookup

Could not get jedis from the pool.