0. stats
show db stats
db.grades.stats()
1. create index
db.students.ensureIndex({class:1,student_name:1})
unique index
db.students.ensureIndex({class:1,student_name:1},{unique:true})
http://docs.mongodb.org/manual/tutorial/create-an-index/
2. show all indexes in current DB
db.system.indexes.find()
3. show index for a collection
db.grades.getIndexes()
4. delete index
db.grades.dropIndex({"student_id":1})
5. sparse index
only create index on documents which has this key, document that does not has key "title" will be omitted.
db.people.ensureIndex( { title : 1 } , { sparse : 1 } )
6. hint: specify the index to use
use no index
db.people.find().hint({$natural:1})
db.people.find().hint({'title':1}) // btree index
7. geospatial index/ 2d index
db.loc.insert({"loc":[10,10]})
db.loc.ensureIndex({"loc":'2d',type:1})
$near: find nearest neighbor
db.loc.find({"loc":{$near:[10,10]}})
8. text search
insert
db.text.insert({"words":"apple banana peach"})
db.text.insert({"words":"apple pig"})
create text index
db.text.ensureIndex({"words":"text"})
text search
db.text.find({$text:{$search:"apple"}})
show score for search
db.text.find({$text:{$search:"apple"}},{score:{$meta:"textScore"}}).sort({scor {$meta:"textScore"}})
9. Profiling
http://docs.mongodb.org/manual/tutorial/manage-the-database-profiler/
db.getProfilingLevel()
db.getProfilingStatus()
{ "was" : 0, "slowms" : 100 }
set profiling
db.setProfilingLevel(2)
show profiling
db.system.profile.find().pretty()