Show reverse direction in DecompressChunk EXPLAIN (#8001)

Only in verbose or non-text modes. This is useful for debugging.

Author: akuzm

tsl/src/nodes/decompress_chunk/exec.c

@@ -524,7 +524,12 @@ decompress_chunk_explain(CustomScanState *node, List *ancestors, ExplainState *e
 			ExplainPropertyBool("Batch Sorted Merge", dcontext->batch_sorted_merge, es);
 		}
 
-		if (es->analyze && (es->verbose || es->format != EXPLAIN_FORMAT_TEXT))
+		if (dcontext->reverse)
+		{
+			ExplainPropertyBool("Reverse", dcontext->reverse, es);
+		}
+
+		if (es->analyze)
 		{
 			ExplainPropertyBool("Bulk Decompression",
 								chunk_state->decompress_context.enable_bulk_decompression,

tsl/test/expected/compression_sequence_num_removal.out

@@ -84,21 +84,25 @@ ORDER BY device_id DESC, time DESC;
    Sort Key: _hyper_1_1_chunk.device_id DESC, _hyper_1_1_chunk."time" DESC
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_1_chunk
          Output: _hyper_1_1_chunk."time", _hyper_1_1_chunk.device_id, _hyper_1_1_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_5_chunk_device_id__ts_meta_min_1__ts_meta__idx on _timescaledb_internal.compress_hyper_2_5_chunk
                Output: compress_hyper_2_5_chunk._ts_meta_count, compress_hyper_2_5_chunk.device_id, compress_hyper_2_5_chunk._ts_meta_min_1, compress_hyper_2_5_chunk._ts_meta_max_1, compress_hyper_2_5_chunk."time", compress_hyper_2_5_chunk.val
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_2_chunk
          Output: _hyper_1_2_chunk."time", _hyper_1_2_chunk.device_id, _hyper_1_2_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_6_chunk_device_id__ts_meta_min_1__ts_meta__idx on _timescaledb_internal.compress_hyper_2_6_chunk
                Output: compress_hyper_2_6_chunk._ts_meta_count, compress_hyper_2_6_chunk.device_id, compress_hyper_2_6_chunk._ts_meta_min_1, compress_hyper_2_6_chunk._ts_meta_max_1, compress_hyper_2_6_chunk."time", compress_hyper_2_6_chunk.val
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_3_chunk
          Output: _hyper_1_3_chunk."time", _hyper_1_3_chunk.device_id, _hyper_1_3_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_7_chunk_device_id__ts_meta_min_1__ts_meta__idx on _timescaledb_internal.compress_hyper_2_7_chunk
                Output: compress_hyper_2_7_chunk._ts_meta_count, compress_hyper_2_7_chunk.device_id, compress_hyper_2_7_chunk._ts_meta_min_1, compress_hyper_2_7_chunk._ts_meta_max_1, compress_hyper_2_7_chunk."time", compress_hyper_2_7_chunk.val
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_4_chunk
          Output: _hyper_1_4_chunk."time", _hyper_1_4_chunk.device_id, _hyper_1_4_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_8_chunk_device_id__ts_meta_min_1__ts_meta__idx on _timescaledb_internal.compress_hyper_2_8_chunk
                Output: compress_hyper_2_8_chunk._ts_meta_count, compress_hyper_2_8_chunk.device_id, compress_hyper_2_8_chunk._ts_meta_min_1, compress_hyper_2_8_chunk._ts_meta_max_1, compress_hyper_2_8_chunk."time", compress_hyper_2_8_chunk.val
-(18 rows)
+(22 rows)
 
 SELECT * FROM hyper
 ORDER BY device_id DESC, time DESC;
@@ -217,21 +221,25 @@ ORDER BY device_id DESC, time DESC;
    Sort Key: _hyper_1_1_chunk.device_id DESC, _hyper_1_1_chunk."time" DESC
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_1_chunk
          Output: _hyper_1_1_chunk."time", _hyper_1_1_chunk.device_id, _hyper_1_1_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_5_chunk_device_id__ts_meta_sequence_num_idx on _timescaledb_internal.compress_hyper_2_5_chunk
                Output: compress_hyper_2_5_chunk._ts_meta_count, compress_hyper_2_5_chunk.device_id, compress_hyper_2_5_chunk._ts_meta_min_1, compress_hyper_2_5_chunk._ts_meta_max_1, compress_hyper_2_5_chunk."time", compress_hyper_2_5_chunk.val, compress_hyper_2_5_chunk._ts_meta_sequence_num
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_2_chunk
          Output: _hyper_1_2_chunk."time", _hyper_1_2_chunk.device_id, _hyper_1_2_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_6_chunk_device_id__ts_meta_min_1__ts_meta__idx on _timescaledb_internal.compress_hyper_2_6_chunk
                Output: compress_hyper_2_6_chunk._ts_meta_count, compress_hyper_2_6_chunk.device_id, compress_hyper_2_6_chunk._ts_meta_min_1, compress_hyper_2_6_chunk._ts_meta_max_1, compress_hyper_2_6_chunk."time", compress_hyper_2_6_chunk.val
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_3_chunk
          Output: _hyper_1_3_chunk."time", _hyper_1_3_chunk.device_id, _hyper_1_3_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_7_chunk_device_id__ts_meta_sequence_num_idx on _timescaledb_internal.compress_hyper_2_7_chunk
                Output: compress_hyper_2_7_chunk._ts_meta_count, compress_hyper_2_7_chunk.device_id, compress_hyper_2_7_chunk._ts_meta_min_1, compress_hyper_2_7_chunk._ts_meta_max_1, compress_hyper_2_7_chunk."time", compress_hyper_2_7_chunk.val, compress_hyper_2_7_chunk._ts_meta_sequence_num
    ->  Custom Scan (DecompressChunk) on _timescaledb_internal._hyper_1_4_chunk
          Output: _hyper_1_4_chunk."time", _hyper_1_4_chunk.device_id, _hyper_1_4_chunk.val
+         Reverse: true
          ->  Index Scan Backward using compress_hyper_2_8_chunk_device_id__ts_meta_min_1__ts_meta__idx on _timescaledb_internal.compress_hyper_2_8_chunk
                Output: compress_hyper_2_8_chunk._ts_meta_count, compress_hyper_2_8_chunk.device_id, compress_hyper_2_8_chunk._ts_meta_min_1, compress_hyper_2_8_chunk._ts_meta_max_1, compress_hyper_2_8_chunk."time", compress_hyper_2_8_chunk.val
-(18 rows)
+(22 rows)
 
 SELECT * FROM hyper
 ORDER BY device_id DESC, time DESC;