| 9.2.2.5.3. + | ||
|---|---|---|
 | 9.2.2.5. Boolean operators |  |
| 9.2.2.5.3. + | ||
|---|---|---|
| | 9.2.2.5. Boolean operators | |
The “+” or required operator requires that the term after the “+” symbol exist somewhere in the document.
To search for documents that must contain “learning” and may contain “federation” use the query:
+learning federation |
| |  | |
| 9.2.2.5.2. AND |  | 9.2.2.5.4. NOT |