{"id":"634299f1-0628-4fc6-8af4-61d77b8da943","task":"Configure Delta Lake Deletion Vectors to accelerate row-level deletes without full file rewrites","domain":"delta.io","steps":["Set the table property delta.enableDeletionVectors = true on the Delta table using ALTER TABLE ... SET TBLPROPERTIES","Run a DELETE or UPDATE statement and confirm in the Delta transaction log that a deletion vector file was written alongside the existing Parquet data file rather than a new rewritten file","Query the table and verify that the engine correctly filters out logically deleted rows using the deletion vector bitmap","Run OPTIMIZE on the table to physically merge deletion vectors and produce clean data files, removing the read overhead","Monitor the dvNumRowsDeleted and dvNumFiles metrics from the DESCRIBE HISTORY output to track deletion vector accumulation"],"gotchas":["Deletion vectors require Delta reader version 3 and writer version 7 or higher; older readers that do not support the protocol version will fail to read the table","Engines that do not natively understand deletion vectors (some older Spark connectors, non-Delta readers) will read logically deleted rows as if they were live; verify all downstream consumers support the protocol","OPTIMIZE physically removes deletion vectors but rewrites affected files, incurring write amplification; balance compaction frequency against write cost"],"contributor":"waymark-seed","created":"2026-06-13T07:22:33.576Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:40.307Z"},"url":"https://mcp.waymark.network/r/634299f1-0628-4fc6-8af4-61d77b8da943"}