org.apache.flink.api.java.io.jdbc.split

Class NumericBetweenParametersProvider

java.lang.Object

org.apache.flink.api.java.io.jdbc.split.NumericBetweenParametersProvider

All Implemented Interfaces:

ParameterValuesProvider

public class NumericBetweenParametersProvider
extends Object
implements ParameterValuesProvider

This query parameters generator is an helper class to parameterize from/to queries on a numeric column. The generated array of from/to values will be equally sized to fetchSize (apart from the last one), ranging from minVal up to maxVal.

For example, if there's a table BOOKS with a numeric PK id, using a query like:

   SELECT * FROM BOOKS WHERE id BETWEEN ? AND ?
 

You can take advantage of this class to automatically generate the parameters of the BETWEEN clause, based on the passed constructor parameters.

Constructor Summary

Constructors

Constructor and Description
NumericBetweenParametersProvider(long fetchSize, long minVal, long maxVal) NumericBetweenParametersProvider constructor.

Method Summary

Modifier and Type	Method and Description
Serializable[][]	getParameterValues() Returns the necessary parameters array to use for query in parallel a table.

Methods inherited from class java.lang.Object

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

Constructor Detail

NumericBetweenParametersProvider

public NumericBetweenParametersProvider(long fetchSize,
                                        long minVal,
                                        long maxVal)

NumericBetweenParametersProvider constructor.

Parameters:

fetchSize - the max distance between the produced from/to pairs

minVal - the lower bound of the produced "from" values

maxVal - the upper bound of the produced "to" values

Method Detail

getParameterValues

public Serializable[][] getParameterValues()

Description copied from interface: ParameterValuesProvider

Returns the necessary parameters array to use for query in parallel a table.

Specified by:

getParameterValues in interface ParameterValuesProvider