--- mongo version 9 Fri May 13 08:00:35 -0700 2011
+++ mongo version 10 Wed May 02 03:00:48 -0700 2012
@@ -1,147 +1,147 @@
CONSOLE COMMANDS
help show all the console commands (same as this section)
show dbs show database names
show collections show collections in current database
show users show users in current database
show profile show most recent system.profile entries with time >= 1ms
use <db name> set curent database to <db name>
db.help() help on DB methods
db.foo.help() help on collection methods
db.foo.find() list objects in collection foo
db.foo.find({a:1}) list objects in foo where a == 1
it result of last line evaluated; use to further iterate
DATABASE METHODS
db.addUser(username, password)
db.auth(username, password)
db.cloneDatabase(fromhost)
db.commandHelp(name) // returns the help for the command
db.copyDatabase(fromdb, todb, fromhost)
db.createCollection(name, { size : ..., capped : ..., max : ... } )
db.currentOp() // displays the current operation in the db
db.dropDatabase()
db.eval(func, args) // run code server-side
db.getCollection(cname) // same as db['cname'] or db.cname
db.getCollectionNames()
db.getLastError() // just returns the err msg string
db.getLastErrorObj() // return full status object
db.getMongo() // get the server connection object
db.getMongo().setSlaveOk() // allow this connection to read from the nonmaster
member of a replica pair
db.getName()
db.getPrevError()
db.getProfilingLevel()
db.getReplicationInfo()
db.getSisterDB(name) // get the db at the same server as this onew
db.killOp() // kills the current operation in the db
db.printCollectionStats()
db.printReplicationInfo()
db.printSlaveReplicationInfo()
db.printShardingStatus()
db.removeUser(username)
db.repairDatabase()
db.resetError()
db.runCommand(cmdObj) // run a database command. if cmdObj is a string, turns
it into {cmdObj:1}
db.setProfilingLevel(level) // 0=off 1=slow 2=all
db.shutdownServer()
db.version() // current version of the server
COLLECTION METHODS
db.foo.count()
db.foo.dataSize()
db.foo.distinct( key ) // eg. db.foo.distinct( 'x' )
db.foo.drop() // drop the collection
db.foo.dropIndex(name)
db.foo.dropIndexes()
db.foo.ensureIndex(keypattern,options) // options should be an object with
these possible fields: name, unique, dropDups
db.foo.find( [query] , [fields]) // first parameter is an optional query
filter.
// second parameter is optional set of fields
to return.
// e.g. db.foo.find( { x : 77 } , { name : 1
, x : 1 } )
db.foo.find(...).count()
db.foo.find(...).limit(n)
db.foo.find(...).skip(n)
db.foo.find(...).sort(...)
db.foo.findOne([query])
db.foo.getDB() // get DB object associated with collection
db.foo.getIndexes()
db.foo.group( { key : ..., initial: ..., reduce : ...[, cond: ...] } )
db.foo.mapReduce( mapFunction , reduceFunction , <optional params> )
db.foo.remove(query)
db.foo.renameCollection( newName ) // renames the collection
db.foo.save(obj)
db.foo.stats()
db.foo.storageSize() // includes free space allocated to this collection
db.foo.totalIndexSize() // size in bytes of all the indexes
db.foo.totalSize() // storage allocated for all data and indexes
db.foo.update(query, object[, upsert_bool, multi_record_bool])
db.foo.validate() // SLOW
db.foo.getShardVersion() // only for use with sharding
UTILITIES
mongodump -d database_name -o /some/directory
mongorestore -d database_name /some/directory
EXAMPLES
Inserting Data
> j = { name: "mongo"};
{"name" : "mongo"}
> t = { x : 3 };
{ "x" : 3 }
> db.things.save(j);
> db.things.save(t);
Accessing Data from a Query
var cursor = db.things.find();
while (cursor.hasNext()) { print(tojson(cursor.next())); }
Retrieving Data with Javascript functions
db.things.find().forEach( function(x) { printjson(x);});
select * from things where name="mongo"
db.things.find({name:"mongo"}).forEach(printjson);
select * from things where x=4
db.things.find({x:4}).forEach(printjson);
select j from things where x=4
db.things.find({x:4}, {j:true}).forEach(printjson);
order by
- db.things.find().sort(x:1) // ascending
- db.things.find().sort(x:-1) // descending
+ db.things.find().sort({x:1}) // ascending
+ db.things.find().sort({x:-1}) // descending
limit 1
var mongo = db.things.findOne({name:"mongo"});
print(tojson(mongo));
limit(x)
db.things.find().limit(3);
update users set api_token = 'snafu' where _id = "fubar";
db.users.update( { "_id" : "fubar" }, { $set : { "api_token" : "snafu" } },
false );
update or insert users set api_token = 'snafu' where _id = "fubar";
db.users.update( { "_id" : "fubar" }, { $set : { "api_token" : "snafu" } },
true );
Rename all fields in a collection
db.users.update( {}, { $rename : {"old_field_name" : "new_field_name"}},
false, true);
MORE HELP
In addition to the general "help" command in mongo, you can call help on db
and db.whatever to see a summary of methods available.
MongoDB Manual: http://www.mongodb.org/display/DOCS/Manual
