table

Class MapIndexExample

java.lang.Object

table.MapIndexExample

public class MapIndexExample
extends Object

This is an example of using map indexes. It creates a simple table with a map of properties field. An index is created on that map. The example demonstrates how to create and use such an index. The index is on the map key plus the map values. This 2-component index allows the following index scan operations:

1. Specific key plus specific value
2. Specific key plus range of values
3. Range of keys

It is not possible to search a range of values without a specific key because of the way multi-component indexes are stored.

The map information used is artificial and comprises a small set of keys that are known. Using a map allows addition or removal of a new key string without schema evolution, which is an advantage over using a fixed record instead.

To build (from the examples/table directory):

   javac -d . -cp .:<path-to-kvclient.jar> MapIndexExample.java

To run (a KVLite or other store instance must be running on the specified host and port, under the store name. All parameters are required.

   java -cp .:<path-to-kvclient.jar> table.MapIndexExample \
     -host <hostName> \
     -port <port> \
     -store <storeName>
     [-clean]

If -clean is specified the example will remove any existing table (and data) before and after it is run.

Method Summary

Methods

Modifier and Type	Method and Description
static void	main(String[] args)

Methods inherited from class java.lang.Object

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

Method Detail

main

public static void main(String[] args)