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DescribeDeltaDetailCommand

= DescribeDeltaDetailCommand (And DescribeDeltaDetailCommandBase)

DescribeDeltaDetailCommand represents DESCRIBE DETAIL SQL command at execution (and is <> when DeltaSqlAstBuilder is requested to <>).

Like DESCRIBE DETAIL SQL command, DescribeDeltaDetailCommand accepts either a <> or a <> (e.g. '/tmp/delta/t1' or ++delta./tmp/delta/t1++)

(DESC | DESCRIBE) DETAIL (path | table)

[[demo]] .DESCRIBE DETAIL SQL Command's Demo

val q = sql("DESCRIBE DETAIL '/tmp/delta/users'")
scala> q.show
+------+--------------------+----+-----------+--------------------+--------------------+-------------------+----------------+--------+-----------+----------+----------------+----------------+
|format|                  id|name|description|            location|           createdAt|       lastModified|partitionColumns|numFiles|sizeInBytes|properties|minReaderVersion|minWriterVersion|
+------+--------------------+----+-----------+--------------------+--------------------+-------------------+----------------+--------+-----------+----------+----------------+----------------+
| delta|3799b291-dbfa-4f8...|null|       null|file:/tmp/delta/u...|2020-01-06 17:08:...|2020-01-06 17:12:28| [city, country]|       4|       2581|        []|               1|               2|
+------+--------------------+----+-----------+--------------------+--------------------+-------------------+----------------+--------+-----------+----------+----------------+----------------+

[[implementations]] DescribeDeltaDetailCommand is the default and only known <> in Delta Lake.

[[DescribeDeltaDetailCommandBase]] DescribeDeltaDetailCommandBase is an extension of the RunnableCommand contract (from Spark SQL) for <>.

TIP: Read up on https://jaceklaskowski.gitbooks.io/mastering-spark-sql/spark-sql-LogicalPlan-RunnableCommand.html[RunnableCommand] in https://bit.ly/spark-sql-internals[The Internals of Spark SQL] online book.

== [[creating-instance]] Creating DescribeDeltaDetailCommand Instance

DescribeDeltaDetailCommand takes the following to be created:

  • [[path]] Table path
  • [[tableIdentifier]] Table identifier (e.g. t1 or ++delta./tmp/delta/t1++)

== [[run]] Running Command -- run Method

[source, scala]

run(sparkSession: SparkSession): Seq[Row]

NOTE: run is part of the RunnableCommand contract to...FIXME.

run...FIXME


Last update: 2020-09-24