Package org.apache.drill.exec.physical.rowSet

Provides a set of tools to work with row sets.

See: Description

Interface Summary

Interface	Description
RowSet	A row set is a collection of rows stored as value vectors.
RowSet.ExtendableRowSet	Single row set which is empty and allows writing.
RowSet.HyperRowSet	Row set comprised of multiple single row sets, along with an indirection vector (SV4).
RowSet.HyperRowSetBuilder
RowSet.SingleRowSet	Row set that manages a single batch of rows.
RowSetReader	Reader for all types of row sets: those with or without a selection vector.
RowSetWriter	Interface for writing values to a row set.

Class Summary

Class	Description
AbstractRowSet	Basic implementation of a row set for both the single and multiple (hyper) varieties, both the fixed and extensible varieties.
AbstractSingleRowSet	Base class for row sets backed by a single record batch.
DirectRowSet	Implementation of a single row set with no indirection (selection) vector.
DirectRowSet.RowSetWriterBuilder
HyperRowIndex	Read-only row index into the hyper row set with batch and index values mapping via an SV4.
HyperRowSetImpl	Implements a row set wrapper around a collection of "hyper vectors." A hyper-vector is a logical vector formed by a series of physical vectors stacked on top of one another.
HyperRowSetImpl.HyperRowSetBuilderImpl
IndirectRowIndex	Reader index that points to each row indirectly through the selection vector.
IndirectRowSet	Single row set coupled with an indirection (selection) vector, specifically an SV2.
RowSetBuilder	Fluent builder to quickly build up an row set (record batch) programmatically.
RowSetFormatter	Helper class to obtain string representation of RowSet.
RowSetReaderImpl	Reader implementation for a row set.
RowSets
RowSetWriterImpl	Implementation of a row set writer.

Package org.apache.drill.exec.physical.rowSet Description

Provides a set of tools to work with row sets. A row set is a batch of Drill vectors, often called a "record batch." However, a record batch, in Drill, means not just the data, but also an operator on that data. The classes here work with the data itself, and can be used to test implementations of things such as code generated classes and so on.

The classes include tools for reading and writing row sets, comparing actual and expected results, and so on.

Drill defines a variety of record batch semantics, modeled here as distinct row set classes:

RowSet

The abstract definition of a row set that defines operations available on all row sets.

SingleRowSet (abstract)

Represents a row set that contains a single record batch (the typical case.

DirectRowSet

A read-only single row set without a selection vector.

IndirectRowSet

A read-only, single row set with an SV2. Note that the SV2 itself is writable (such as for sorting.)

ExtendableRowSet

A write-only, single row set used to create a new row set. Because of the way Drill sets row counts, an extendable row set cannot be read; instead at the completion of the write the extendable row set becomes a direct or indirect row set.

HyperRowSet

A read-only row set made up of a collection of record batches, indexed via an SV4.

This package contains a number of helper classes:

RowSetWriter

Writes data into an extendable row set.

RowSetReader

Reads data from any but an extendable row set.

RowSetFormatter

Prints a row set to stdout in a CSV-like form for easy debugging.

RowSetBuilder

Creates and populates a row set in a fluent builder style.