1.更新colltions
{$set:{ "Status" : "交易成功",}}2.模糊查询List类型的colltions
{"sys_category":new RegExp("213.*")} 3.MongoDB强制使用主库，主库优先等配置说明
只需要修改readPreference配置，举例如下 具体参数参考以下。PRIMARY: Read from the primary. This is the default, and provides the strongest consistency. If no primary is available, raise AutoReconnect.PRIMARY_PREFERRED: Read from the primary if available, or if there is none, read from a secondary.SECONDARY: Read from a secondary. If no secondary is available, raise AutoReconnect.SECONDARY_PREFERRED: Read from a secondary if available, otherwise from the primary.NEAREST: Read from any member.
