Redis is used where IO may be a bottleneck. It stores data that is always read and written from the hard disk to reduce hard disk IO overhead. It can be regarded as a cache. Redis was born to improve IO speed. MongoDB can store massive amounts of data. After all, it is a hard disk database, which is different from Redis. The speed is also very fast (if the index is built correctly), of course, this is compared with other hard disk databases.
Since I started using the non-relational style, I have never used the relational style again.
It is estimated that pure KV cannot satisfy it. After all, query is also a rigid requirement.
I think apps and e-commerce can do this 1. You can use mongodb for all product data, including attribute search 2 Product price data can also be used with mongo, including complex promotions, full discounts, restrictions, and group purchases 3 Order data also needs to use mysql relational data 4 User data can actually be generated using mysql, 5 comments using mongo
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1.redis is similar to membercache and can be used as a sustainable cache. It is rarely used as a database alone
2.mongodb is similar to mysql and has good scalability
3. Systems involving associative operations
4. Yes, but they will be used in conjunction
5. Yes, in some data
Redis is used where IO may be a bottleneck. It stores data that is always read and written from the hard disk to reduce hard disk IO overhead. It can be regarded as a cache. Redis was born to improve IO speed.
MongoDB can store massive amounts of data. After all, it is a hard disk database, which is different from Redis. The speed is also very fast (if the index is built correctly), of course, this is compared with other hard disk databases.
Since I started using the non-relational style, I have never used the relational style again.
It is estimated that pure KV cannot satisfy it. After all, query is also a rigid requirement.
@michel yang: It’s MemoryCache, right?
I think apps and e-commerce can do this
1. You can use mongodb for all product data, including attribute search
2 Product price data can also be used with mongo, including complex promotions, full discounts, restrictions, and group purchases
3 Order data also needs to use mysql relational data
4 User data can actually be generated using mysql,
5 comments using mongo