Make fast scan code mode clean

dbms/src/Storages/DeltaMerge/DMSegmentThreadInputStream.h

@@ -47,8 +47,7 @@ class DMSegmentThreadInputStream : public IProfilingBlockInputStream
         const RSOperatorPtr & filter_,
         UInt64 max_version_,
         size_t expected_block_size_,
-        bool is_raw_,
-        bool do_delete_mark_filter_for_raw_,
+        ReadMode read_mode_,
         const int extra_table_id_index,
         const TableID physical_table_id,
         const String & req_id)
@@ -60,8 +59,7 @@ class DMSegmentThreadInputStream : public IProfilingBlockInputStream
         , header(toEmptyBlock(columns_to_read))
         , max_version(max_version_)
         , expected_block_size(expected_block_size_)
-        , is_raw(is_raw_)
-        , do_delete_mark_filter_for_raw(do_delete_mark_filter_for_raw_)
+        , read_mode(read_mode_)
         , extra_table_id_index(extra_table_id_index)
         , physical_table_id(physical_table_id)
         , log(Logger::get(NAME, req_id))
@@ -102,26 +100,35 @@ class DMSegmentThreadInputStream : public IProfilingBlockInputStream
                 }
 
                 cur_segment = task->segment;
-                if (is_raw)
+                auto block_size = std::max(expected_block_size, static_cast<size_t>(dm_context->db_context.getSettingsRef().dt_segment_stable_pack_rows));
+                switch (read_mode)
                 {
-                    cur_stream = cur_segment->getInputStreamRaw(
+                case ReadMode::Normal:
+                    cur_stream = cur_segment->getInputStream(
                         *dm_context,
                         columns_to_read,
                         task->read_snapshot,
                         task->ranges,
                         filter,
-                        do_delete_mark_filter_for_raw);
-                }
-                else
-                {
-                    cur_stream = cur_segment->getInputStream(
+                        max_version,
+                        block_size);
+                    break;
+                case ReadMode::Fast:
+                    cur_stream = cur_segment->getInputStreamFast(
                         *dm_context,
                         columns_to_read,
                         task->read_snapshot,
                         task->ranges,
                         filter,
-                        max_version,
-                        std::max(expected_block_size, static_cast<size_t>(dm_context->db_context.getSettingsRef().dt_segment_stable_pack_rows)));
+                        block_size);
+                    break;
+                case ReadMode::Raw:
+                    cur_stream = cur_segment->getInputStreamRaw(
+                        *dm_context,
+                        columns_to_read,
+                        task->read_snapshot,
+                        task->ranges);
+                    break;
                 }
                 LOG_TRACE(log, "Start to read segment, segment={}", cur_segment->simpleInfo());
             }
@@ -172,8 +179,7 @@ class DMSegmentThreadInputStream : public IProfilingBlockInputStream
     Block header;
     const UInt64 max_version;
     const size_t expected_block_size;
-    const bool is_raw;
-    const bool do_delete_mark_filter_for_raw;
+    const ReadMode read_mode;
     // position of the ExtraPhysTblID column in column_names parameter in the StorageDeltaMerge::read function.
     const int extra_table_id_index;
 

dbms/src/Storages/DeltaMerge/DeltaMergeStore.cpp

@@ -845,7 +845,7 @@ void DeltaMergeStore::compact(const Context & db_context, const RowKeyRange & ra
     }
 }
 
-// Read data without mvcc filtering && delete mark != 0 filtering.
+// Read data without mvcc filtering.
 // just for debug
 // readRaw is called under 'selraw  xxxx'
 BlockInputStreams DeltaMergeStore::readRaw(const Context & db_context,
@@ -902,8 +902,7 @@ BlockInputStreams DeltaMergeStore::readRaw(const Context & db_context,
         EMPTY_FILTER,
         std::numeric_limits<UInt64>::max(),
         DEFAULT_BLOCK_SIZE,
-        /* is_raw = */ true,
-        /* do_delete_mark_filter_for_raw = */ false,
+        /* read_mode */ ReadMode::Raw,
         std::move(tasks),
         after_segment_read,
         req_info);
@@ -931,8 +930,7 @@ BlockInputStreams DeltaMergeStore::readRaw(const Context & db_context,
                 EMPTY_FILTER,
                 std::numeric_limits<UInt64>::max(),
                 DEFAULT_BLOCK_SIZE,
-                /* is_raw_ */ true,
-                /* do_delete_mark_filter_for_raw_ */ false, // don't do filter based on del_mark = 1
+                /* read_mode */ ReadMode::Raw,
                 extra_table_id_index,
                 physical_table_id,
                 req_info);
@@ -986,8 +984,7 @@ BlockInputStreams DeltaMergeStore::read(const Context & db_context,
         filter,
         max_version,
         expected_block_size,
-        /* is_raw = */ is_fast_scan,
-        /* do_delete_mark_filter_for_raw = */ is_fast_scan,
+        /* read_mode = */ is_fast_scan ? ReadMode::Fast : ReadMode::Normal,
         std::move(tasks),
         after_segment_read,
         log_tracing_id);
@@ -1015,8 +1012,7 @@ BlockInputStreams DeltaMergeStore::read(const Context & db_context,
                 filter,
                 max_version,
                 expected_block_size,
-                /* is_raw_= */ is_fast_scan,
-                /* do_delete_mark_filter_for_raw_= */ is_fast_scan,
+                /* read_mode = */ is_fast_scan ? ReadMode::Fast : ReadMode::Normal,
                 extra_table_id_index,
                 physical_table_id,
                 log_tracing_id);

dbms/src/Storages/DeltaMerge/Segment.cpp

@@ -507,64 +507,58 @@ BlockInputStreamPtr Segment::getInputStreamForDataExport(const DMContext & dm_co
     return data_stream;
 }
 
-/// we will call getInputStreamRaw in two condition:
-///     1. Using 'selraw xxxx' statement, which is always in test for debug. (when filter_delete_mark = false)
-///        In this case, we will read all the data without mvcc filtering,
-///        del_mark != 0 filtering and sorted merge.
-///        We will just read all the data and return.
-///     2. We read in fast mode. (when filter_delete_mark = true)
-///        In this case, we will read all the data without mvcc filtering and sorted merge,
-///        but we will do del_mark != 0 filtering.
-BlockInputStreamPtr Segment::getInputStreamRaw(const DMContext & dm_context,
-                                               const ColumnDefines & columns_to_read,
-                                               const SegmentSnapshotPtr & segment_snap,
-                                               const RowKeyRanges & data_ranges,
-                                               const RSOperatorPtr & filter,
-                                               bool filter_delete_mark,
-                                               size_t expected_block_size)
+/// We call getInputStreamFast when we read in fast mode.
+/// In this case, we will read all the data in delta and stable, and then merge them without sorting.
+/// Besides, we will do del_mark != 0 filtering to drop the deleted rows.
+/// In conclusion, the output is unsorted, and does not do mvcc filtering.
+BlockInputStreamPtr Segment::getInputStreamFast(
+    const DMContext & dm_context,
+    const ColumnDefines & columns_to_read,
+    const SegmentSnapshotPtr & segment_snap,
+    const RowKeyRanges & data_ranges,
+    const RSOperatorPtr & filter,
+    size_t expected_block_size)
 {
-    /// Now, we use filter_delete_mark to determine whether it is in fast mode or just from `selraw * xxxx`
-    /// But this way seems not to be robustness enough, maybe we need another flag?
     auto new_columns_to_read = std::make_shared<ColumnDefines>();
 
     // new_columns_to_read need at most columns_to_read.size() + 2, due to may extra insert into the handle column and del_mark column.
     new_columns_to_read->reserve(columns_to_read.size() + 2);
 
     new_columns_to_read->push_back(getExtraHandleColumnDefine(is_common_handle));
-    if (filter_delete_mark)
-    {
-        new_columns_to_read->push_back(getTagColumnDefine());
-    }
-
-    bool enable_handle_clean_read = filter_delete_mark;
-    bool enable_del_clean_read = filter_delete_mark;
+    new_columns_to_read->push_back(getTagColumnDefine());
+
+    /// When we read in fast mode, we can try to do the following optimization:
+    /// 1. Handle Column Optimization:
+    ///     when the columns_to_read does not include HANDLE_COLUMN,
+    ///     we can try to skip reading the handle column if the pack's handle range is fully within read range.
+    ///     Thus, in this case, we set enable_handle_clean_read = true.
+    /// 2. Del Column Optimization:
+    ///    when the columns_to_read does not include TAG_COLUMN,
+    ///    we can try to skip reading the del column if the pack has no deleted rows.
+    ///    Thus, in this case, we set enable_del_clean_read = true.
+    /// 3. Version Column Optimization:
+    ///    if the columns_to_read does not include VERSION_COLUMN,
+    ///    we don't need to read version column, thus we don't force push version column into new_columns_to_read.
+
+    bool enable_handle_clean_read = true;
+    bool enable_del_clean_read = true;
 
     for (const auto & c : columns_to_read)
     {
-        if (c.id != EXTRA_HANDLE_COLUMN_ID)
+        if (c.id == EXTRA_HANDLE_COLUMN_ID)
         {
-            if (filter_delete_mark && c.id == TAG_COLUMN_ID)
-            {
-                enable_del_clean_read = false;
-            }
-            else
-            {
-                new_columns_to_read->push_back(c);
-            }
+            enable_handle_clean_read = false;
+        }
+        else if (c.id == TAG_COLUMN_ID)
+        {
+            enable_del_clean_read = false;
         }
         else
         {
-            enable_handle_clean_read = false;
+            new_columns_to_read->push_back(c);
         }
     }
 
-    /// when we read in fast mode, if columns_to_read does not include EXTRA_HANDLE_COLUMN_ID,
-    /// we can try to use clean read to make optimization in stable part.
-    /// when the pack is under totally data_ranges and has no rows whose del_mark = 1 --> we don't need read handle_column/tag_column/version_column
-    /// when the pack is under totally data_ranges and has rows whose del_mark = 1 --> we don't need read handle_column/version_column
-    /// others --> we don't need read version_column
-    /// Thus, in fast mode, if we don't need read handle_column, we set enable_handle_clean_read as true.
-    /// If we don't need read del_column, we set enable_del_clean_read as true
     BlockInputStreamPtr stable_stream = segment_snap->stable->getInputStream(
         dm_context,
         *new_columns_to_read,
@@ -573,25 +567,69 @@ BlockInputStreamPtr Segment::getInputStreamRaw(const DMContext & dm_context,
         std::numeric_limits<UInt64>::max(),
         expected_block_size,
         /* enable_handle_clean_read */ enable_handle_clean_read,
-        /* is_fast_scan */ filter_delete_mark,
+        /* is_fast_scan */ true,
         /* enable_del_clean_read */ enable_del_clean_read);
 
     BlockInputStreamPtr delta_stream = std::make_shared<DeltaValueInputStream>(dm_context, segment_snap->delta, new_columns_to_read, this->rowkey_range);
 
     delta_stream = std::make_shared<DMRowKeyFilterBlockInputStream<false>>(delta_stream, data_ranges, 0);
     stable_stream = std::make_shared<DMRowKeyFilterBlockInputStream<true>>(stable_stream, data_ranges, 0);
 
-    if (filter_delete_mark)
+    delta_stream = std::make_shared<DMDeleteFilterBlockInputStream>(delta_stream, columns_to_read, dm_context.tracing_id);
+    stable_stream = std::make_shared<DMDeleteFilterBlockInputStream>(stable_stream, columns_to_read, dm_context.tracing_id);
+
+    BlockInputStreams streams;
+
+    if (dm_context.read_delta_only)
     {
-        delta_stream = std::make_shared<DMDeleteFilterBlockInputStream>(delta_stream, columns_to_read, dm_context.tracing_id);
-        stable_stream = std::make_shared<DMDeleteFilterBlockInputStream>(stable_stream, columns_to_read, dm_context.tracing_id);
+        streams.push_back(delta_stream);
+    }
+    else if (dm_context.read_stable_only)
+    {
+        streams.push_back(stable_stream);
     }
     else
     {
-        delta_stream = std::make_shared<DMColumnProjectionBlockInputStream>(delta_stream, columns_to_read);
-        stable_stream = std::make_shared<DMColumnProjectionBlockInputStream>(stable_stream, columns_to_read);
+        streams.push_back(delta_stream);
+        streams.push_back(stable_stream);
     }
+    return std::make_shared<ConcatBlockInputStream>(streams, dm_context.tracing_id);
+}
+
+/// We call getInputStreamRaw in 'selraw xxxx' statement, which is always in test for debug.
+/// In this case, we will read all the data without mvcc filtering and sorted merge.
+BlockInputStreamPtr Segment::getInputStreamRaw(const DMContext & dm_context,
+                                               const ColumnDefines & columns_to_read,
+                                               const SegmentSnapshotPtr & segment_snap,
+                                               const RowKeyRanges & data_ranges,
+                                               size_t expected_block_size)
+{
+    auto new_columns_to_read = std::make_shared<ColumnDefines>();
+
+    new_columns_to_read->push_back(getExtraHandleColumnDefine(is_common_handle));
+
+    for (const auto & c : columns_to_read)
+    {
+        if (c.id != EXTRA_HANDLE_COLUMN_ID)
+            new_columns_to_read->push_back(c);
+    }
+
+    BlockInputStreamPtr stable_stream = segment_snap->stable->getInputStream(
+        dm_context,
+        *new_columns_to_read,
+        data_ranges,
+        EMPTY_FILTER,
+        std::numeric_limits<UInt64>::max(),
+        expected_block_size,
+        /* enable_handle_clean_read */ false);
+
+    BlockInputStreamPtr delta_stream = std::make_shared<DeltaValueInputStream>(dm_context, segment_snap->delta, new_columns_to_read, this->rowkey_range);
+
+    delta_stream = std::make_shared<DMRowKeyFilterBlockInputStream<false>>(delta_stream, data_ranges, 0);
+    stable_stream = std::make_shared<DMRowKeyFilterBlockInputStream<true>>(stable_stream, data_ranges, 0);
 
+    delta_stream = std::make_shared<DMColumnProjectionBlockInputStream>(delta_stream, columns_to_read);
+    stable_stream = std::make_shared<DMColumnProjectionBlockInputStream>(stable_stream, columns_to_read);
 
     BlockInputStreams streams;
 
@@ -611,12 +649,12 @@ BlockInputStreamPtr Segment::getInputStreamRaw(const DMContext & dm_context,
     return std::make_shared<ConcatBlockInputStream>(streams, dm_context.tracing_id);
 }
 
-BlockInputStreamPtr Segment::getInputStreamRaw(const DMContext & dm_context, const ColumnDefines & columns_to_read, bool filter_delete_mark)
+BlockInputStreamPtr Segment::getInputStreamRaw(const DMContext & dm_context, const ColumnDefines & columns_to_read)
 {
     auto segment_snap = createSnapshot(dm_context, false, CurrentMetrics::DT_SnapshotOfReadRaw);
     if (!segment_snap)
         return {};
-    return getInputStreamRaw(dm_context, columns_to_read, segment_snap, {rowkey_range}, EMPTY_FILTER, filter_delete_mark);
+    return getInputStreamRaw(dm_context, columns_to_read, segment_snap, {rowkey_range});
 }
 
 SegmentPtr Segment::mergeDelta(DMContext & dm_context, const ColumnDefinesPtr & schema_snap) const

dbms/src/Storages/DeltaMerge/Segment.h

@@ -179,19 +179,24 @@ class Segment : private boost::noncopyable
         size_t expected_block_size = DEFAULT_BLOCK_SIZE,
         bool reorganize_block = true) const;
 
-    BlockInputStreamPtr getInputStreamRaw(
+    BlockInputStreamPtr getInputStreamFast(
         const DMContext & dm_context,
         const ColumnDefines & columns_to_read,
         const SegmentSnapshotPtr & segment_snap,
         const RowKeyRanges & data_ranges,
         const RSOperatorPtr & filter,
-        bool filter_delete_mark = true,
         size_t expected_block_size = DEFAULT_BLOCK_SIZE);
 
     BlockInputStreamPtr getInputStreamRaw(
         const DMContext & dm_context,
         const ColumnDefines & columns_to_read,
-        bool filter_delete_mark = false);
+        const SegmentSnapshotPtr & segment_snap,
+        const RowKeyRanges & data_ranges,
+        size_t expected_block_size = DEFAULT_BLOCK_SIZE);
+
+    BlockInputStreamPtr getInputStreamRaw(
+        const DMContext & dm_context,
+        const ColumnDefines & columns_to_read);
 
     /// For those split, merge and mergeDelta methods, we should use prepareXXX/applyXXX combo in real production.
     /// split(), merge() and mergeDelta() are only used in test cases.

dbms/src/Storages/DeltaMerge/SegmentReadTaskPool.cpp

@@ -100,14 +100,35 @@ BlockInputStreamPtr SegmentReadTaskPool::buildInputStream(SegmentReadTaskPtr & t
     MemoryTrackerSetter setter(true, mem_tracker.get());
     auto seg = t->segment;
     BlockInputStreamPtr stream;
-    if (is_raw)
+    auto block_size = std::max(expected_block_size, static_cast<size_t>(dm_context->db_context.getSettingsRef().dt_segment_stable_pack_rows));
+    switch (read_mode)
     {
-        stream = seg->getInputStreamRaw(*dm_context, columns_to_read, t->read_snapshot, t->ranges, filter, do_range_filter_for_raw);
-    }
-    else
-    {
-        auto block_size = std::max(expected_block_size, static_cast<size_t>(dm_context->db_context.getSettingsRef().dt_segment_stable_pack_rows));
-        stream = seg->getInputStream(*dm_context, columns_to_read, t->read_snapshot, t->ranges, filter, max_version, block_size);
+    case ReadMode::Normal:
+        stream = seg->getInputStream(
+            *dm_context,
+            columns_to_read,
+            t->read_snapshot,
+            t->ranges,
+            filter,
+            max_version,
+            block_size);
+        break;
+    case ReadMode::Fast:
+        stream = seg->getInputStreamFast(
+            *dm_context,
+            columns_to_read,
+            t->read_snapshot,
+            t->ranges,
+            filter,
+            block_size);
+        break;
+    case ReadMode::Raw:
+        stream = seg->getInputStreamRaw(
+            *dm_context,
+            columns_to_read,
+            t->read_snapshot,
+            t->ranges);
+        break;
     }
     LOG_FMT_DEBUG(log, "getInputStream succ, pool_id={} segment_id={}", pool_id, seg->segmentId());
     return stream;