Adding a Step that Loads a Data Set

Follow the instructions below to add a step that loads a new data set into a data layer in a graphmart. The data set to load must be available in the Catalog.

Note: You cannot clone and reuse existing Load Data Steps. The steps below guide you through creating new Load Data Steps.

  1. In the Anzo console, expand the Blend menu and click Graphmarts.
  2. On the Graphmarts screen, click the name of the graphmart that you want to change.
  3. Click the Data Layers tab. Anzo displays the existing data layers.
  4. Click the ellipses () on the layer for which you want to create a step, and then select Add Step/View. Anzo opens the Add step dialog box.

  5. Select Load Data Step on the Add screen, and then click OK. Anzo opens the Create load data step screen.

  6. On the Create screen, type a name for the step in the Title field and add an optional description in the Description field.
  7. Click the Linked Dataset drop-down list and select the data set that you want this step to load. The list displays all of the data sets in the Catalog, including the system data sets.
  8. By default the Enabled option is selected, indicating that the step is enabled and will run when the layer is loaded. If you want to disable the step so that it is not processed, clear the Enabled check box.
  9. Optional: Filter the load data. If you want to load all of the statements in the linked data set, proceed to step 9. If you do not want to load all of the data in the data set, follow the instructions in this step to filter the load data.

    Anzo provides two options for filtering data. To view the instructions for an option, click the How do I... text for that option:

    1. Exclude certain triples from the load by selecting predicates to filter out (masked predicates).
      1. Click the Filter tab at the top of the load data step screen. Anzo displays the filter options:

      2. Select the Multiple Select radio button.
      3. Click the Masked Predicate drop-down list and select a predicate to add it to the Masked Predicate field. Repeat this step to mask additional predicates. You can remove a property from the masked list by clicking the X to the right of the predicate name.
    2. If the data set is a graph source (file-based linked data set), you can hand-pick the data to load by writing a query that inserts specific values or filters out certain values.
      1. Click the Filter tab at the top of the load data step screen. Anzo displays the filter options:

      2. Select the Query radio button. Anzo displays a text box under the Query field.

      3. Type a SPARQL INSERT query in the Query box. For example, you can use the following format to filter out properties from the files.

        Note: Including the ${targetGraph} and ${usingSources} parameters are required.

        INSERT {
  GRAPH ${targetGraph}{ 
    ?s ?p ?o.
  }
}
${usingSources}
WHERE {
  ?s ?p ?o .
  FILTER EXISTS { ?s a ?type . }
  FILTER(?type = <URI>)
}

        Important: In load filter queries, URIs are not supported in the object position. To specify a URI as an object, include the standard ?s ?p ?o triple pattern in the WHERE clause and then apply FILTER statements with URIs as needed. URIs are supported in the subject or predicate position.

        For example, the following query filters the data in a sample data set that includes information about people and the events they buy tickets for. The WHERE clause filters the data to load only the triples that are related to person1 (personid=1):

        INSERT { GRAPH ${targetGraph} {
  ?s ?p ?o
 }
}
${usingSources}
WHERE {
  ?s ?p ?o ;
  <http://cambridgesemantics.com/ont/autogen/Fu/Tickit_Data#tickit_users_personid> ?id .
  FILTER (?id=1)
}
  10. Click Save to add the step to the data layer. Anzo adds the step as the last step in the layer. If you want to change the order of the steps, click the black bar on the left side of a step and drag it up or down.

Example Load Data Step

The example below creates a step that loads an additional "Tickit" data set to the Movie Data graphmart:

The example excludes triples that include user's credit card numbers from the load by masking the "card" predicate:

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