Creating queries

About this task

Creating a query involves the creation of at least three separate objects: a QueryDef Object, a QueryFilterNode Object, and a ResultSet Object. More complex queries might also involve the creation of additional QueryFilterNode objects.

Procedure

To create a query, follow these steps:
  1. Create a QueryDef object and fill it with the search parameters.

    To create this object, use the BuildQuery method of the Session object.

    Note: You use the BuildQuery method to build a query and not the BuildSQLQuery method. The BuildSQLQuery method generates a ResultSet object directly from an SQL query string.
  2. Use the methods of QueryDef to add search criteria and to specify the fields of each record you want the query to return.
  3. Create a ResultSet object to hold the returned data.

    To create this object, call the BuildResultSet method of the Session object. On creation, the ResultSet object creates a set of internal data structures using the information in the QueryDef object as a template. When the query is run, the ResultSet object fills these data structures with data from the query.

  4. Run the query by calling the ResultSet object's Execute method.
  5. Access the data using other methods of this object. (For more information, see "Navigating through the result set".)

Results

Note: If you use the BuildSQLQuery method to create a query based on SQL syntax, your query string must contain all of the desired search parameters. The BuildSQLQuery method returns a ResultSet object directly, instead of returning a QueryDef object.