#include #include #include #include namespace DB { Block MergeTreeBlockOutputStream::getHeader() const { return metadata_snapshot->getSampleBlock(); } void MergeTreeBlockOutputStream::writePrefix() { /// Only check "too many parts" before write, /// because interrupting long-running INSERT query in the middle is not convenient for users. storage.delayInsertOrThrowIfNeeded(); } void MergeTreeBlockOutputStream::write(const Block & block) { auto part_blocks = storage.writer.splitBlockIntoParts(block, max_parts_per_block, metadata_snapshot); for (auto & current_block : part_blocks) { Stopwatch watch; MergeTreeData::MutableDataPartPtr part = storage.writer.writeTempPart(current_block, metadata_snapshot, optimize_on_insert); /// If optimize_on_insert setting is true, current_block could become empty after merge /// and we didn't create part. if (!part) continue; /// Part can be deduplicated, so increment counters and add to part log only if it's really added if (storage.renameTempPartAndAdd(part, &storage.increment, nullptr, storage.getDeduplicationLog())) { PartLog::addNewPart(storage.getContext(), part, watch.elapsed()); /// Initiate async merge - it will be done if it's good time for merge and if there are space in 'background_pool'. storage.background_executor.triggerTask(); } } } }