ShowColumns¶

ShowColumns is a StatementWithExtendedClause that represents the following KSQL statement:

DESCRIBE sourceName EXTENDED?

ShowColumns is executed using ListSourceExecutor.

Creating Instance¶

ShowColumns takes the following to be created:

• NodeLocation
• Source Name
• isExtended flag

ShowColumns is created when:

• AstBuilder.Visitor is requested to parse DESCRIBE SOURCE statement

isExtended Flag¶

ShowColumns is given isExtended flag when created.

The isExtended flag is used when:

• ListSourceExecutor is requested to columns

accept¶

<R, C> R accept(
  AstVisitor<R, C> visitor,
  C context)

accept is part of the Statement abstraction.

accept requests the AstVisitor to visitShowColumns (with this ShowColumns instance).