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Kristina Chodorow
MapReduce, Geospatial Indexes, and Other Cool Features
connecting to your mongod
connecting to your mongod
you
connecting to your mongod
you
mongod
mongod
mongod
mongodupdate query insertinsert query
mongod
driver
driver
insert
query
mongod
driver
insert
query
mongod
driver
insertgetlasterror
mongod
driver
insertgetlasterror
Dwight @ 3:15Farallon Room
replication
insert this
all set
insert this
all set
make sure two slaves have this
all set
make sure two slaves have this
> db.runCommand(... getlasterror : 1... )
> db.runCommand(... getlasterror : 1,... w : 3... )
> db.runCommand(... getlasterror : 1,... w : 500... )
> db.runCommand(... getlasterror : 1,... w : 500,... wtimeout : 3000... )
> db.runCommand(... getlasterror : 1,... fsync : true... )
some internals
insertupdateremovequeryget more
Operations:
insertupdateremovequeryget more
Operations:
insertupdateremovequeryget more
Operations:
insertupdateremovequeryget more
Operations:
insertupdateremovequeryget more
Operations:
insertupdateremovequeryget more
Operations:
insertupdateremovequeryget more
Operations:
get help
$ mongoMongoDB shell version 1.5.1url: testconnecting to: testtype "help" for help>
$ mongoMongoDB shell version 1.5.1url: testconnecting to: testtype "help" for help>
> db.help()DB methods:
db.addUser()db.auth()db.cloneDatabase()db.commandHelp()db.copyDatabase()db.createCollection()db.currentOp()...
> db.foo.help()DBCollection help
db.foo.count()db.foo.dataSize()db.foo.distinct()db.foo.drop()db.foo.dropIndex()db.foo.dropIndexes()...
> var cursor = db.foo.find()> cursor.help()DBQuery help
.sort()
.limit()
.skip()
.count()
.size()
...
http://api.mongodb.org/js
> db.foo.count()40>
> db.foo.count()40> db.foo.count
> db.foo.count()40> db.foo.countfunction(x) return this.find(x).count();;
>
> db.foo.count()40> db.foo.countfunction(x)
return this.find(x).count();;> var cursor = db.foo.find()>
> db.foo.count()40> db.foo.countfunction(x)
return this.find(x).count();;> var cursor = db.foo.find()> cursor.count
> cursor.countfunction(applySkipLimit) var cmd = count : this._collection.getName();;if (this._query) if (this._special) cmd.query = this._query.query;;
else cmd.query = this._query;;
cmd.fields = this._fields || ;;if (applySkipLimit)
if (this._limit) cmd.limit = this._limit;;
...
function(x) // prep cmd...
// run commandvar res = this._db.runCommand(cmd);;
// return result...
> db.runCommand(count : "foo")
"n" : 40,"ok" : 1
>
> db.runCommand(listCommands : 1)
> db.runCommand(listCommands : 1)
"commands" : "$eval" : ...,"assertinfo : ...,"authenticate" : ...,"buildinfo" : ...,"clean" : ...,"clone" : ...,"cloneCollection" : ...,"cloneCollectionAsCapped" : ...,"closeAllDatabases" : ...,...
> db.runCommand(... datasize : collectionName)
> db.runCommand(... datasize : collectionName)
> db.runCommand(... dbstats : 1)
> db.commandHelp("distinct")help for: distinct:
distinct : 'collection name',key : 'a.b'
>
> db.commandHelp("distinct")help for: distinct:
distinct : 'collection name',key : 'a.b'
> db.commandHelpfunction(name)
var c = ;;c[name] = 1;;c.help = true;;return this.runCommand(c).help;;
>
> db.runCommand("count" : 1, ... "help" : true)
> db.runCommand("count" : 1, ... "help" : true)help for: count: no help defined>
$
> db.blog.posts.find(... _id : 123,... comments : 1)
> db.blog.posts.find(... _id : 123,... comments : $slice : 10)
> db.blog.posts.find(... _id : 123,... comments : $slice : [20, 10])
> db.blog.posts.find(... _id : 123,... comments : $slice : -10)
> db.blog.posts.find(... _id : 123,... comments : $slice : [-20, 10])
> db.blog.posts.find(... comments : ... date : $gt : today,... votes : $gte : 10... )
> db.blog.posts.find(... 'comments.date' : $gt : today,... 'comments.votes' : $gte : 10... )
> db.blog.posts.find(... comments : $elemMatch : ... date : $gt : today,... votes : $gte : 10... )
Types
minKey
maxKey
MapReduce
_id : 123,name : "Fred",email : "[email protected]"
_id : 456,name : "Paul",phone : "555-5555",picture : BinData
_id : 789,email : "[email protected]",
_id 40name 32email 20phone 2picture 17pet 3friends 40hobbies 6favorites 12notes 14
_id : 123,name : "Fred",email : "[email protected]"
1
11
1
1
1
_id
name
12
12
cluck cluck
12
map = function() for (var key in this) emit(key, 1);;
reduce = function(prev, current) var count = 0;;for (var egg in current) count += current[egg];;
return count;;
EB D FA C
EB D FA C
_id : C, value :
_id : F, value :
_id : E, value :_id : A, value :
EB D FA C
_id : B, value : _id : D, value :
GridFS
Indexes
> db.users.find(... date : new Date("10/3/2010"))
> db.users.ensureIndex(... date : 1)
Dates, timestamps, ObjectIds
Aaron @ 3:15Niantic Room
indexing
Geospatial Indexes
> db.map.ensureIndex(location : "2d")>
> db.map.insert(location : [-40, 78])>
> db.map.insert(location : [-40, 78])> db.map.insert(location : ... x : -40, ... y : 78)>
> db.map.insert(location : [-40, 78])> db.map.insert(location : ... x : -40, ... y : 78)> db.map.insert(location : ... longitude : -40, ... latitude : 78)>
> db.map.find(location : ... $near : [-40, 77])
> db.map.find(location : ... $near : [-40, 77])->limit(10)
> db.map.ensureIndex(... location : "2d",... user : 1);;
1 degree of longitude at the equator:
1 degree of longitude at the equator:
1 degree of longitude near the poles:
Eliot @ 10:15Gateway Room
geospatial
please help document stuff!
http://cookbook.mongodb.org
want to work on mongodb?
http://www.10gen.com/jobs
thank you!
@kchodorow
http://www.snailinaturtleneck.com
