【MongoDB】The basic operation of Index in MongoDB
In the past four blogs, we attached importance to the index, including description and comparison with usage of index. Now in this blog, we will mainly focus on the basic operation of index. such query, remove ,repair and so on.
1. View Index
getIndexes could view all the indexes in the collections.
2. Delete index
delete all the indexes: db.test.dropIndexes()
delete one index: db.test.dropIndex({name:1})
use the command to delete index:
db.runCommand({dropIndexes:"test",index:{name:1}})
3. rebuild index
db.test.reIndex() is equalant to db.runCommand({reIndex:'test'})
Attention:This operation need to add the lock into the document, so if the collection was filled with a large number of data, this operation would take much time.
if using repair to fix database, the database will rebuild the index.