DescribeTableCommand Logical Command¶

DescribeTableCommand is a LeafRunnableCommand (indirectly as DescribeCommandBase) that represents a DescribeRelation at execution (and hence DESCRIBE TABLE SQL statement).

Creating Instance¶

DescribeTableCommand takes the following to be created:

• TableIdentifier
• TablePartitionSpec
• isExtended flag
• Output Attributes

DescribeTableCommand is created when:

• ResolveSessionCatalog logical analysis rule is executed (to resolve DescribeRelation logical operator)

Detailed Table Information¶

describeFormattedTableInfo(
  table: CatalogTable,
  buffer: ArrayBuffer[Row]): Unit

describeFormattedTableInfo...FIXME

describeFormattedTableInfo is used when:

• DescribeTableCommand is executed (with a table and isExtended enabled)