feat(storage): analyze table noscan #18254
Merged
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Summary
This PR introduces a lightweight
ANALYZE TABLE
mode that avoids scanning all rows.Instead of reading the entire table, it traverses all segments and blocks, incrementally merging NDV (number of distinct values) from the block level to the segment level, and finally to the snapshot level.
This reduces memory and CPU usage significantly by eliminating full table decoding and recomputation.
Syntax:
The NOSCAN syntax is inspired by implementations in Spark and DB2.
Behavior:
New tables no longer need to run
ANALYZE TABLE ... NOSCAN
. Their snapshots will automatically merge NDV information during creation.Existing tables can be updated with a one-time execution of:
Tests
Type of change
This change is