Description

Uses the Pentaho Metadata Query Language (MQL) to perform a query against Pentaho Metadata.

Inputs and Outputs

MQL - The MQL query to be performed.

Output Name - The name of the resulting output dataset. Following actions can refer to the data set using this name.

MQL Designer

The MQL Designer facilitates the authoring of MQL through the use of a simple to use UI. In order to use the MQL Designer from within the design studio, the action sequence being edited must reside inside a valid pentaho solution. At the root of the solution there must exist a metadata.xmi file that is properly configured.

MQL Preview

The MQL Preview button allows the user to preview the data that will be returned from the MQL Query. In order for the preview to function properly, your Pentaho BI Server must be running. Prior to release 1.6.M5 preview was not functional. A preliminary fix, requiring manual configuration of JNDI connections, has been made in version 1.6.M5 that corrects this issue. To enable MQL Preview functionality create the following directory <workspace-dir>/.metadata/.plugins/org.pentaho.designstudio.editors.actionsequence/simple-jndi. In this director create a jdbc.properties file and define the jndi connection name used in the metadata file. A sample jndi definition is shown below:

SampleData/type=javax.sql.DataSource
SampleData/driver=org.hsqldb.jdbcDriver
SampleData/url=jdbc:hsqldb:hsql://localhost/sampledata
SampleData/user=pentaho_user
SampleData/password=password

You'll also have to make sure that the JDBC driver jar file for the database you are trying to use is on your Java classpath. The easiest way to do this is to drop the jar in the <JAVA_HOME>/lib directory.

Once this is done MQL queries can be previewed.

Future releases of the design studio will enable the user to define their JNDI connections using the Pentaho preferences dialog (Refer to JIRA case #PDS-277).