Combined queries
- 2. Agenda 2 1. Definition 2. Examples 3. Resources
- 3. • Definition – Queries that work together to create a single result – Similar to SAAL (in colleague) • Take one population of subtractaddjoin from the original query 3
- 4. 3 types 1.union; Web Intelligence takes the all the data from both queries, eliminates duplicate rows, and builds a combined data set. Union All allows duplicates 2. intersection; Web Intelligence returns the data that is common to both queries. 3. minus; Web Intelligence returns the data in the first query that does not appear in the second 4
- 5. • 3 types 5
- 6. • Caveats – Make sure your 2 queries have the same number of output items in the results objects – You can double click on the combined query to change from Union to Minus or Intersection 6
- 7. Demo 7
- 8. NOTE re Sub Query vs Combined query; A subquery is a more flexible kind of query filter that allows you to restrict values in more sophisticated ways than with an ordinary query filter. Subqueries are more powerful than ordinary query filters for the following reasons: • They allow you to compare the values of the object whose values are used to restrict the query with values from other objects. • They allow you to restrict the values returned by the subquery with a WHERE clause. 8