Columns added in the future will always be added after the last column. A few of the other columns are not available if you write into a Delta table using the following methods:. |version| timestamp|userId|userName|operation| operationParameters| job|notebook|clusterId|readVersion| isolationLevel|isBlindAppend| operationMetrics| User-defined commit metadata if it was specified Metrics of the operation (for example, number of rows and files modified.) Version of the table that was read to perform the write operation. ID of the cluster on which the operation ran. Parameters of the operation (for example, predicates.)ĭetails of the job that ran the operation.ĭetails of notebook from which the operation was run. Table version generated by the operation. The output of the history operation has the following columns. In addition to the table schema and sample data, you can click the History tab to see the table history that displays with DESCRIBE HISTORY. See the Delta Lake API documentation for Scala/Java/Python syntax details.ĭata Explorer provides a visual view of this detailed table information and history for Delta tables. 
DESCRIBE HISTORY '/data/events/' - get the full history of the tableĭESCRIBE HISTORY '/data/events/' LIMIT 1 - get the last operation onlyįor Spark SQL syntax details, see DESCRIBE HISTORY.
By default table history is retained for 30 days. The operations are returned in reverse chronological order.
You can retrieve information on the operations, user, timestamp, and so on for each write to a Delta tableīy running the history command. You can use history information to audit operations or query a table at a specific point in time. Each operation that modifies a Delta Lake table creates a new table version.
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