Database Names

ArangoDB will always start up with a default database, named _system. Users can create additional databases in ArangoDB, provided the database names conform to the selected naming convention for databases.

In ArangoDB versions before 3.9 there was only the traditional naming convention available. Since ArangoDB version 3.9 there is also the extended naming convention, that is disabled by default. It can be enabled on an installation by setting the startup option --database.extended-names-databases to true.

The extended naming convention is an experimental feature in ArangoDB 3.9, but will become the norm in a future version. Drivers and client applications should be prepared for this feature.

The restrictions of the two naming conventions are:

  • For the traditional naming convention:
    • Database names must only consist of the letters a to z (both lower and upper case allowed), the numbers 0 to 9, and the underscore (_) or dash (-) symbols. This also means that any non-ASCII database names are not allowed.
    • Database names must always start with a letter. Database names starting with an underscore are considered to be system databases, and users should not create or delete those.
    • The maximum allowed length of a database name is 64 bytes.
    • Database names are case-sensitive.
  • For the extended naming convention:
    • Names can consist of most UTF-8 characters, such as Japanese or Arabic letters, emojis, letters with accentuation. Some ASCII characters are disallowed, but less compared to the traditional naming convention.
    • Names cannot contain the characters / or : at any position, nor any control characters (below ASCII code 32), such as \n, \t, \r, and \0.
    • Spaces are accepted, but only in between characters of the name. Leading or trailing spaces are not allowed.
    • . (dot), _ (underscore) and the numeric digits 0-9 are not allowed as first character, but at later positions.
    • Database names are case sensitive.
    • Database names containing UTF-8 characters must be NFC-normalized. Non-normalized names will be rejected by arangod.
    • The maximum length of a database name is 128 bytes after normalization. As a UTF-8 character may consist of multiple bytes, this does not necessarily equate to 128 characters.

    Example database names that can be used with the extended naming convention: "España", "😀", "犬", "كلب", "@abc123", "København", "München", "Россия", "abc? <> 123!"

While it is possible to change the value of the --database.extended-names-databases option from false to true to enable extended names, the reverse is not true. Once the extended names have been enabled they will remain permanently enabled so that existing databases with extended names remain accessible.

Please be aware that dumps containing extended database names cannot be restored into older versions that only support the traditional naming convention. In a cluster setup, it is required to use the same database naming convention for all Coordinators and DB-Servers of the cluster. Otherwise the startup will be refused. In DC2DC setups it is also required to use the same database naming convention for both datacenters to avoid incompatibilities.