MongoDB Index Use

for (Var i=0;i<10000;i++) {

Db.user.insert ({name: "User" +i,age:i})

} Add so much data

Db.user.find ({name: "user100"}) did not add an index to scan all data

Db.user.find ({name: "user100"}). Explain () can view information about using the index, such as the number of query bars, the time of the query

Db.user.ensureIndex ({name:1}) create index for name

Db.user.stats () See how the index is related

Db.user.find ({name: "user100"}) after the index is added, the scan line finds the

Db.user.dropIndex ({name:1}) Delete Index Table

If you delete a collection, name all the indexes on this collection are also deleted

Create a unique index, you cannot create an element with the same name value

Db.user.createIndex ({name:1},{unique:true})

MongoDB Index Use