Release Notes for MongoDB 1.2.x

New Features

  • More indexes per collection
  • Faster index creation
  • Map/Reduce
  • Stored JavaScript functions
  • Configurable fsync time
  • Several small features and fixes

DB Upgrade Required

There are some changes that will require doing an upgrade if yourprevious version is <= 1.0.x. If you’re already using a version >= 1.1.xthen these changes aren’t required. There are 2 ways to do it:

  • —upgrade
    • stop your mongod process
    • run ./mongod —upgrade
    • start mongod again
  • use a slave
    • start a slave on a different port and data directory
    • when its synced, shut down the master, and start the new slave onthe regular port.

Ask in the forums or IRC for more help.

Replication Changes

  • There have been minor changes in replication. If you are upgrading amaster/slave setup from <= 1.1.2 you have to update the slave first.

mongoimport

  • mongoimportjson has been removed and is replaced withmongoimport that can do json/csv/tsv

field filter changing

  • We’ve changed the semantics of the field filter a little bit.Previously only objects with those fields would be returned. Now thefield filter only changes the output, not which objects are returned.If you need that behavior, you can use $exists