cursorOpen method

Future<Pointer<MDB_cursor>> cursorOpen(Pointer<MDB_txn> txn, { String? dbName, })

Opens a new cursor for the specified database

Parameters:

• txn - Active transaction
• dbName - Optional named database

Returns a cursor that must be closed with cursorClose

Example:

final txn = await db.txnStart();
try {
  final cursor = await db.cursorOpen(txn);
  try {
    // Use cursor...
  } finally {
    db.cursorClose(cursor);
  }
  await db.txnCommit(txn);
} catch (e) {
  await db.txnAbort(txn);
  rethrow;
}

Implementation

Future<Pointer<MDB_cursor>> cursorOpen(
  Pointer<MDB_txn> txn, {
  String? dbName,
}) async {
  if (!isInitialized) throw StateError(_errDbNotInitialized);

  final dbi = await _getDatabase(txn, name: dbName);
  final cursorPtr = calloc<Pointer<MDB_cursor>>();

  try {
    final result = _lib.mdb_cursor_open(txn, dbi, cursorPtr);
    if (result != 0) {
      throw LMDBException('Failed to open cursor', result);
    }
    return cursorPtr.value;
  } finally {
    calloc.free(cursorPtr);
  }
}