Delta table properties reference

Delta Lake reserves Delta table properties starting with delta. These properties may have specific meanings, and affect behaviors when these properties are set. Available Delta table properties include:

Property	Description	Data Type	Default
delta.appendOnly	true for this Delta table to be append-only. If append-only, existing records cannot be deleted, and existing values cannot be updated. See Table properties.	Boolean	false
delta.checkpoint.writeStatsAsJson	true for Delta Lake to write file statistics in checkpoints in JSON format for the stats column.	Boolean	true
delta.checkpoint.writeStatsAsStruct	true for Delta Lake to write file statistics to checkpoints in struct format for the stats_parsed column and to write partition values as a struct for partitionValues_parsed.	Boolean	(none)
delta.compatibility.symlinkFormatManifest.enabled	true for Delta Lake to configure the Delta table so that all write operations on the table automatically update the manifests. See Step 3: Update manifests.	Boolean	false
delta.dataSkippingNumIndexedCols	The number of columns for Delta Lake to collect statistics about for data skipping. A value of -1 means to collect statistics for all columns. Updating this property does not automatically collect statistics again; instead, it redefines the statistics schema of the Delta table. For example, it changes the behavior of future statistics collection (such as during appends and optimizations) as well as data skipping (such as ignoring column statistics beyond this number, even when such statistics exist).	Int	32
delta.deletedFileRetentionDuration	The shortest duration for Delta Lake to keep logically deleted data files before deleting them physically. This is to prevent failures in stale readers after compactions or partition overwrites. This value should be large enough to ensure that: 1. It is larger than the longest possible duration of a job if you run VACUUM when there are concurrent readers or writers accessing the Delta table. 2. If you run a streaming query that reads from the table, that the query does not stop for longer than this value. Otherwise, the query may not be able to restart, as it must still read old files. See Data retention.	CalendarInterval	interval 1 week
delta.enableChangeDataFeed	true to enable change data feed. See Enable change data feed.	Boolean	false
delta.logRetentionDuration	How long the history for a Delta table is kept. Each time a checkpoint is written, Delta Lake automatically cleans up log entries older than the retention interval. If you set this property to a large enough value, many log entries are retained. This should not impact performance as operations against the log are constant time. Operations on history are parallel but will become more expensive as the log size increases. See Data retention.	CalendarInterval	interval 30 days
delta.minReaderVersion	The minimum required protocol reader version for a reader that allows to read from this Delta table. See Table protocol versioning.	Int	1
delta.minWriterVersion	The minimum required protocol writer version for a writer that allows to write to this Delta table. See Table protocol versioning.	Int	2
delta.setTransactionRetentionDuration	The shortest duration within which new snapshots will retain transaction identifiers (for example, SetTransactions). When a new snapshot sees a transaction identifier older than or equal to the duration specified by this property, the snapshot considers it expired and ignores it. The SetTransaction identifier is used when making the writes idempotent. See Idempotent table writes in foreachBatch for details.	CalendarInterval	(none)