Index Server

From this section you can connect to a Scheduler Index server to configure it, manage its indexes and import or export its metadata.

The first step is to provide the connection details (host and port) together with the administration password of the Scheduler Index server, as shown in the following image.

Scheduler Index server connection

Scheduler Index server connection

Once connected to the desired Scheduler Index Server, in the top of the page you will see the host and port of the server and three links to connect to another Scheduler Index server, disconnect from the current one and go back to the Administration main screen. In the lower part part of the page you will see three areas: “Index Server Sep-Up”, “Indexes Management” and “Import/Export Backup”, as shown in the following image.

Scheduler Index server main page

Scheduler Index server connection

Index Server Set-Up

From this configuration area you can access to the section “Connectivity”. From this section you can configure the ports used by the server and the administration password.

Server connectivity details

The Scheduler Index server uses three port numbers for client communications: the server execution port, the server stoppage port, and the auxiliary port.

Important

When the Scheduler Index server and the Administration Tool or other clients are installed in different machines, you may need to change the interface where the server listens to connections. To change this, open the Denodo Control Center, open the “Configuration” dialog and change the “RMI Host” of the “JVM Options”. See more details in the section Denodo Platform Configuration of the Installation Guide. The reason for this is that in some environments, when listening to ‘localhost’, the server does not allow connections from remote hosts.

Note

Where the connections between clients and the Scheduler Index server has to go through a firewall, this must be configured to allow access to the execution port and the auxiliary port.

The port changes will take effect the next time the Scheduler Index server restarts.

Change password

To change the administration password you have to provide the current password.

Index Management

From this area you can access to the section “Indexes”. From this section you can manage the indexes of the server.

You will see a table with all the indexes contained in the server. For each index, the table shows its name, the path where its data is stored and the analyzer type used by the index.

Above the table there is an option to enable the filtering (you can filter the indexes searching by name, path and analyzer type), and another option to add a new index. When creating an index you have to provide its name, the path where the index content will be stored and the analyzer type to be used.

Each row of the table has options to remove the index corresponding to that row and to access to its details page. From the details page of an index you can edit it (name, path and analyzer type), remove it or remove the index content.

Note

The analyzer to be used by an index should be selected in accordance with the language expected for the data to be indexed. Stopwords (those words that are very common in the language) will be removed.

Besides, some analyzers use “stemming”. Those analyzers attempt to eliminate the most common morphological endings from the words in a document before it is indexed. The objective is to ensure that a search for a specific keyword also returns the documents that contain other words with the same lexical root. For example, if we look for the word “trade”, documents that contain words such as “trades” or “trading” are also returned.

Stemming techniques may or may not be suitable, depending on the use the application is going to be given. It is also important to bear in mind that stemming techniques are based on a series of general rules that can accept certain exceptions. This means that, in some rare cases, the system can erroneously identify the lexical roots of some words.

Denodo Scheduler Index includes three own different analyzers:

  • standard. This considers the list of stop words in English, but does not use stemming.

  • english. This considers the list of stop words and stemming for English.

  • spanish. This considers the list of stop words and stemming for Spanish.

It also includes some built-in analyzers provided by Lucene for the following languages: Arabic, Armenian, Basque, Brazilian, Bulgarian, Catalan, Chinese, Japanese, Korean, Czech, Danish, Dutch, Finish, French, Galician, German, Greek, Hindi, Hungarian, Indonesian, Irish, Italian, Latvian, Norwegian, Persian, Portuguese, Romanian, Russian, Swedish, Thai, and Turkish. The name of those analyzers in the Web Administration Tool is: <language> (lucene).

Import/Export Backup

From this area, there two options to Import and Export the metadata of the indexes configured in the server.

If you click Import, you will access to a new page to specify a ZIP file containing the metadata of the indexes to import and an option to specify if the already existing indexes should be replaced or not.

If you click Export, you will access to a page to export the metadata of all the indexes of the server as a ZIP file.