Package org.apache.sysds.runtime.io

Class ReaderDelta

java.lang.Object

org.apache.sysds.runtime.io.MatrixReader

org.apache.sysds.runtime.io.ReaderDelta

Direct Known Subclasses:

ReaderDeltaParallel

public class ReaderDelta
extends MatrixReader

Single-threaded native Delta Lake reader for matrices, built on the Spark-free Delta Kernel library. It opens the latest snapshot of a Delta table directory, reads its parquet data files through the kernel's default engine (honoring deletion vectors), and materializes the numeric columns into a dense MatrixBlock.

Only numeric columns (double/float/long/int/short/byte/boolean) are supported, matching the all-double nature of a SystemDS matrix. Dimensions do not need to be known up front: the row count is discovered while scanning and the column count is taken from the table schema.

Constructor Summary

Constructors

Constructor	Description
ReaderDelta()

Method Summary

Modifier and Type	Method	Description
MatrixBlock	readMatrixFromHDFS(String fname, long rlen, long clen, int blen, long estnnz)
MatrixBlock	readMatrixFromInputStream(InputStream is, long rlen, long clen, int blen, long estnnz)

Methods inherited from class org.apache.sysds.runtime.io.MatrixReader

checkValidInputFile

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ReaderDelta

public ReaderDelta()

Method Details

readMatrixFromHDFS

public MatrixBlock readMatrixFromHDFS(String fname,
 long rlen,
 long clen,
 int blen,
 long estnnz)
                               throws IOException,
DMLRuntimeException

Specified by:

readMatrixFromHDFS in class MatrixReader

Throws:

IOException

DMLRuntimeException

readMatrixFromInputStream

public MatrixBlock readMatrixFromInputStream(InputStream is,
 long rlen,
 long clen,
 int blen,
 long estnnz)
                                      throws IOException,
DMLRuntimeException

Specified by:

readMatrixFromInputStream in class MatrixReader

Throws:

IOException

DMLRuntimeException