* Split queries into system and data queries
* System queries are sequentially executed and generate separate transaction deltas
* System transaction try locks for 100ms
* last_commited_system_ts saved to DBMS durability
* Replicating CREATE/DROP DATABASE
* Sending a system snapshot if REPLICA behind
* Passing a copy of the gatekeeper::access as std::any to all functions that could call an async execution
* Removed delete_on_drop flag (we now always delete on drop)
* Using UUID as the directory name for databases
* DBMS durability update (added versioning and salient information)
* Automatic migration from previous version
* Interpreter can run some queries without a target database
* SHOW REPLICA returns the status of the currently active DB
* Returning UUID instead of db name in the RPC responses
* Using UUIDs for database specification in RPC (not name)
* FrequentCheck forces update on reconnect
* TimestampRpc will detect if a replica is behind, and will update client's state
* Safer SLK reads
* Split SHOW DATABASES in two SHOW DATABASES (list of current databases) and SHOW DATABASE a single string naming the current database
---------
Co-authored-by: Gareth Lloyd <gareth.lloyd@memgraph.io>
Fixes root cause of a cascade of failures in replication code:
- Replica handling of deleting an edge is now corrected. Now tolerant of multiple edges of the same relationship type.
- Improved robustness: correct exception handling around failed stream of current WAL file. This now means a REPLICA failure will no longer prevent transactions on MAIN from performing WAL writes.
- Slightly better diagnostic messages, not user friendly but helps get developer to correct root cause quicker.
- Proactively remove vertex+edges during Abort rather than defer to GC to do that work, this included fixing constraints and indexes to be safe.
Co-authored-by: Andreja Tonev <andreja.tonev@memgraph.io>
Concurrent access to the same query module had a race condition on the
pointer that was used to handle the custom memory management. With this
commit, a mapping has been added to keep information about what
thread used the pointer to handle the memory resources. This should be
fine since the respected query executions are running on a dedicated
thread. Access to the mapping itself is threadsafe. A simple RAII
wrapper for the mapping container has also been added for simpler
client-side use.
