GROUP BY clause

Use the GROUP BY clause to aggregate your data by one or more columns. To provide meaningful results of the aggregation, usually, data aggregation is combined with aggregate functions on remaining columns.

Examples of GROUP BY clauses

The following query example shows IP addresses that sent more than 1 million bytes within all flows in a specific time.

SELECT sourceIP, SUM(sourceBytes) 
FROM flows where sourceBytes > 1000000 
GROUP BY sourceIP

The results might look similar to the following output.

-----------------------------------
| sourceIP | SUM_sourceBytes |
-----------------------------------
| 192.0.2.0 | 4282590.0 |
| 10.105.2.10 | 4902509.0 |
| 10.103.70.243 | 2802715.0 |
| 10.103.77.143 | 3313370.0 |
| 10.105.32.29 | 2467183.0 |
| 10.105.96.148 | 8325356.0 |
| 10.103.73.206 | 1629768.0 |
-----------------------------------

However, if you compare this information to a non-aggregated query, the output displays all the IP addresses that are unique, as shown in the following output:

------------------------------
| sourceIP | sourceBytes |
------------------------------
| 192.0.2.0 | 1448629 |
| 10.105.2.10 | 2412426 |
| 10.103.70.243 | 1793095 |
| 10.103.77.143 | 1449148 |
| 10.105.32.29 | 1097523 |
| 10.105.96.148 | 4096834 |
| 192.0.2.0 | 2833961 |
| 10.105.2.10 | 2490083 |
| 10.103.73.206 | 1629768 |
| 10.103.70.243 | 1009620 |
| 10.105.32.29 | 1369660 |
| 10.103.77.143 | 1864222 |
| 10.105.96.148 | 4228522 |
------------------------------

To view the maximum number of events, use the following syntax:

SELECT MAX(eventCount) FROM events

To view the number of average events from a source IP, use the following syntax:

SELECT AVG(eventCount), PROTOCOLNAME(protocolid) 
FROM events 
GROUP BY sourceIP

The output displays the following results:

---------------------------------
| sourceIP | protocol |
---------------------------------
| 192.0.2.0 | TCP.tcp.ip |
| 10.105.2.10 | UDP.udp.ip |
| 10.103.70.243 | UDP.udp.ip |
| 10.103.77.143 | UDP.udp.ip |
| 10.105.32.29 | TCP.tcp.ip |
| 10.105.96.148 | TCP.tcp.ip |
| 192.0.2.0 | TCP.tcp.ip |
| 10.105.2.10 | ICMP.icmp.ip |
---------------------------------