Features listed in this section should no longer be used, because they are considered obsolete and may get removed in a future release. They are currently kept for backward compatibility. There are usually better alternatives to replace the old features with:
MMFiles Storage Engine: The MMFiles storage engine is deprecated starting with version 3.6.0 and it will be removed in a future release. To change your MMFiles storage engine deployment to RocksDB, see: Switch storage engine
We recommend to switch to RocksDB even before the removal of MMFiles. RocksDB is the default storage engine since v3.4.0.
Once the MMFiles engine is removed, all MMFiles specific startup options will also be removed. This will affect the following options:
The collection attributes
pathare only used with MMFiles and are thus also deprecated.
Simple Queries: Idiomatic interface in arangosh to perform trivial queries. They are superseded by AQL queries, which can also be run in arangosh. AQL is a language on its own and way more powerful than Simple Queries could ever be. In fact, the (still supported) Simple Queries are translated internally to AQL, then the AQL query is optimized and run against the database in recent versions, because of better performance and reduced maintenance complexity.
From v3.5.0 on, the system collections
_modulesare not created anymore when the
_systemdatabase is first created (blank new data folder). They are not actively removed, they remain on upgrade or backup restoration from previous versions.
You can still find the Actions documentation in 3.4 or older versions of the documentation.