* 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
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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>
* Interpreter transaction ID decoupled from storage transaction ID
* Transactional scope for indices, statistics and constraints
* Storage::Accessor now has 2 modes (unique and shared)
* Introduced ResourceLock to fix pthread mutex problems
* Split InfoQuery in two: non-transactional SystemInfoQuery and transactional DatabaseInfoQuery
* Replicable and durable statistics
* Bumped WAL/Snapshot versions
* Initial implementation of the Lamport clock
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Co-authored-by: Andreja Tonev <andreja.tonev@memgraph.io>
