LP #1645467: pt-query-digest profile shows incorrect UNION statement

**Reported in Launchpad by monty solomon last update 12-12-2016 12:52:55

Some of the values in the WHERE clause contain the string 'union' and pt-query-digest incorrectly displays that the UNION statement is being used for some items displayed in the response-time profile.

Using pt-query-digest 2.2.19

grep -c UNION slow.log
0

pt-query-digest slow.log

1. Profile
2. Rank Query ID Response time Calls R/Call V/M Item
3. ==== ================== ============= ===== ====== ===== ===============
4. 1 0xBA52E9840CF0EDB3 30.4562 22.6% 216 0.1410 0.00 SELECT UNION rainmaker.puppet_var
5. 6 0x02423A5E62328BD1 5.1513 3.8% 43 0.1198 0.00 SELECT UNION instance_status

1. Query 1: 0.03 QPS, 0.00x concurrency, ID 0xBA52E9840CF0EDB3 at byte 94948916
   SELECT instance_id, name, value FROM rainmaker.puppet_var WHERE (puppet_var.valid_until is null) AND instance_id IN('tasty-union','rough-union'/... omitted 100 items .../)\G