Database Admin

Executes a distributed alignment of the database. It must be executed on the Leader server. The alignment computes a checksum of each file and sends them to the replica nodes. Each replica node will compute the checksum on its own files. The files that are mismatching are requested by the replica to the leader. In the future single pages could be transferred instead of the entire file.

Syntax

The command returns which page have been aligned on each server.

Examples

Change a database setting. You can find the available settings in Settings appendix. The update is persistent.

Syntax

Examples

Executes a backup of the current database. The resulting file is a compressed archive using ZIP as algorithm. The archive contains the database directory without the transaction logs. The backup is executed taking a snapshot of the database at the time the command is executed. Any pending transaction will not be in the backup archive. ArcadeDB allows to execute a non-stop backup of a database while it is used without blocking writes or affecting performance.

Syntax

Examples

Executes an integrity check and in case of a repair of the database. This command analyzes the following things:

When a vertex’s edge list is unreadable (for example a lost or corrupted chunk of the adjacency linked list), the FIX mode does not delete anything: every edge record stores its own endpoint identities, so the adjacency list is rebuilt from the surviving edge records. After the rebuild, a full-scope FIX (no TYPE/BUCKET filter) also reclaims the orphaned edge-list segments the old, unreachable chains left on disk.

The other shape is a dangling reference: an adjacency entry that points at a record which no longer exists, typically left behind by a vertex deleted before 26.8.1, when edge removal became strict. There is nothing to rebuild in that case - the record the entry names is gone - so FIX drops the entry instead.

Since v26.9.1, an application that reaches such a record before the repair has run is told so plainly, and always in the same way. Removing an entry from the edge list of a vertex whose own record is missing, adding one to it, and deleting that vertex outright all raise VertexNotFoundException, a RecordNotFoundException (answered as HTTP 404) that names the vertex and points at CHECK DATABASE FIX. Creating an edge whose endpoint is such a record raises it too, naming the endpoint - which is not the vertex the statement named. It is deliberately not a NeedRetryException: the record is gone rather than temporarily unreadable, so a retry can only fail identically, and a job walking possibly-stale references can skip that entry instead of spending its retry budget and rolling back the whole transaction. An unreadable chunk of a vertex that does exist keeps raising the retryable ConcurrentModificationException described above - the two are told apart by which record the failure names.

A DELETE VERTEX refused this way is refused before it touches anything: the vertex’s record is checked first, so the failure does not cost a walk over an adjacency list that is about to be rolled back.

That up-front check reads the vertex’s record, so deleting a vertex needs the readRecord permission on its type as well as deleteRecord (see groups). This is not a new requirement in practice, since every way of obtaining the vertex in order to delete it already reads it, but a group granting deleteRecord alone now fails at the first statement of the delete rather than part of the way through it.

While the check runs, its progress (current step and percentage) is visible live in the console, in Studio, and through the HTTP progress endpoint. Run FIX in a maintenance window: like every repair, it assumes no concurrent writers.

Syntax

The optional clauses must appear in the order shown above.

The command returns the integrity check report in one record with the fields:

TimeSeries integrity

A TimeSeries type has neither record buckets nor indexes, so it is walked by a pass of its own that reads the three on-disk formats it owns: the mutable bucket (.tstb), the shared tag dictionary (.tstd) and the sealed store (.ts.sealed). The default tier reconciles every header and directory against the data it describes and verifies the CRC32 of every sealed block - which means it reads the whole sealed file, the same cost class as the record scan the check already runs over every bucket. A block is otherwise CRC-checked only on the first read that touches it, so a block nothing queries is a block nothing verifies.

DEEP adds the checks that have to decompress. A CRC proves the bytes are the bytes that were written; it proves nothing about whether they mean what the block claims. Three things every read path answers queries from, without ever looking at a value, are verified only under DEEP:

Each of those, when wrong, produces a wrong answer rather than an error, so nothing else in the engine reports it.

FIX repairs only what is derived and never a sample: the mutable bucket’s page-0 counters, the sealed header’s block count and global timestamp bounds, and the tail of an interrupted sealed append. Those matter beyond tidiness - a wrong global bound is read straight out of the header when the file is opened, so a range query pruned against it silently misses data the file holds, and a tail no reader can see also hides every block appended after it.

A sealed block that fails its CRC, or that DEEP finds inconsistent, is reported and left untouched. It is the only copy of the samples in it, so discarding it is a decision for an operator, who under HA can also rebuild a sealed store by recompacting from the replicated mutable pages.

Examples

Exports a database in the exports directory under the root directory where ArcadeDB is running.

Syntax

Examples

Executes an import of the database into the current one. Usually an import database is executed on an empty database, but it is possible to execute on any database. In case of conflict (unique index key already existent, etc.), the conflicting records will not be imported. The importer automatically recognize the file between the following formats:

Syntax

Examples

See also Importer for a description of the settings.