dimgigov
e1bae0c7a0
- Add docs/ folder with English (en/) and Bulgarian (bg/) documentation - Create index.md with language switching and links - English docs: installation, quickstart, architecture, baraql, storage, schema, lsm, btree, vector, graph, fts, columnar, transactions, distributed, protocol, udf, api-binary, api-http, api-websocket - Bulgarian docs: installation, quickstart, architecture, baraql, schema, lsm, btree, vector, graph, fts, transactions, distributed - Update README license to BSD 3-Clause - Add LICENSE file with BSD 3-Clause text
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Transactions & MVCC
MVCC (Multi-Version Concurrency Control) with snapshot isolation and deadlock detection.
Usage
import barabadb/core/mvcc
var tm = newTxnManager()
let txn = tm.beginTxn()
# Write operations
discard tm.write(txn, "key1", cast[seq[byte]]("value1"))
discard tm.write(txn, "key2", cast[seq[byte]]("value2"))
# Savepoint
tm.savepoint(txn)
discard tm.write(txn, "key3", cast[seq[byte]]("value3"))
discard tm.rollbackToSavepoint(txn) # undo key3
# Commit
discard tm.commit(txn)
Transaction Isolation
BaraDB uses snapshot isolation:
- Readers don't block writers
- Writers don't block readers
- Each transaction sees a consistent snapshot
Deadlock Detection
import barabadb/core/deadlock
var detector = newDeadlockDetector()
if detector.detectCycle(txn1, txn2):
echo "Deadlock detected!"
Write-Ahead Log
import barabadb/storage/wal
var wal = newWAL("./wal")
wal.append(txnId, "SET key value")
wal.flush()
Savepoints
Nested transaction savepoints:
tm.savepoint(txn, "sp1")
# ... operations ...
tm.rollbackToSavepoint(txn, "sp1")