Method scan

src/storage/table/node_group.cpp:187–227

}

NodeGroupScanResult NodeGroup::scan(const Transaction* transaction, TableScanState& state) const {
    // TODO(Guodong): Move the locked part of figuring out the chunked group to initScan.
    const auto lock = chunkedGroups.lock();
    auto& nodeGroupScanState = *state.nodeGroupScanState;
    DASSERT(nodeGroupScanState.chunkedGroupIdx < chunkedGroups.getNumGroups(lock));
    const auto chunkedGroup = chunkedGroups.getGroup(lock, nodeGroupScanState.chunkedGroupIdx);
    if (nodeGroupScanState.nextRowToScan >=
        chunkedGroup->getNumRows() + chunkedGroup->getStartRowIdx()) {
        nodeGroupScanState.chunkedGroupIdx++;
        if (nodeGroupScanState.chunkedGroupIdx >= chunkedGroups.getNumGroups(lock)) {
            return NODE_GROUP_SCAN_EMPTY_RESULT;
        }
        ChunkedNodeGroup* currentChunkedGroup =
            chunkedGroups.getGroup(lock, nodeGroupScanState.chunkedGroupIdx);
        initializeScanStateForChunkedGroup(state, currentChunkedGroup);
    }
    const auto& chunkedGroupToScan =
        *chunkedGroups.getGroup(lock, nodeGroupScanState.chunkedGroupIdx);
    DASSERT(nodeGroupScanState.nextRowToScan >= chunkedGroupToScan.getStartRowIdx());
    const auto rowIdxInChunkToScan =
        nodeGroupScanState.nextRowToScan - chunkedGroupToScan.getStartRowIdx();
    const auto numRowsToScan =
        std::min(chunkedGroupToScan.getNumRows() - rowIdxInChunkToScan, DEFAULT_VECTOR_CAPACITY);
    bool enableSemiMask =
        state.source == TableScanSource::COMMITTED && state.semiMask && state.semiMask->isEnabled();
    if (enableSemiMask) {
        const auto startNodeOffset = nodeGroupScanState.nextRowToScan +
                                     StorageUtils::getStartOffsetOfNodeGroup(state.nodeGroupIdx);
        NodeTable::applySemiMaskFilter(state, startNodeOffset, numRowsToScan,
            state.outState->getSelVectorUnsafe());
        if (state.outState->getSelVector().getSelSize() == 0) {
            state.nodeGroupScanState->nextRowToScan += numRowsToScan;
            return NodeGroupScanResult{nodeGroupScanState.nextRowToScan, 0};
        }
    }
    chunkedGroupToScan.scan(transaction, state, nodeGroupScanState, rowIdxInChunkToScan,
        numRowsToScan);
    const auto startRow = nodeGroupScanState.nextRowToScan;
    nodeGroupScanState.nextRowToScan += numRowsToScan;
    return NodeGroupScanResult{startRow, numRowsToScan};
}

NodeGroupScanResult NodeGroup::scan(Transaction* transaction, TableScanState& state,
    offset_t startOffsetInGroup, offset_t numRowsToScan) const {