Since Mongo is schemaless, there is no need to specify schema, only collections must be created. Same for indexes - these are just classic (B-tree) indexes that work on any field type.
另一个猜测的思路，与审核有关。
，更多细节参见WPS下载最新地址
Surrounded by Formidable RivalsFrom an industry-wide perspective, consumer-grade laser engraving machines are still a “blue ocean.”
At this point, the conclusion is that it really depends.