| Subject | Re: Firebird 2.5: Nested querys help |
|---|---|
| Author | |
| Post date | 2017-08-31T19:01:11Z |
Set, thank you for your help.
I'll like to explain my self better. If having these records:
table_id date_time customer_id other_fields
-------- ---------------- ----------- ------------
001 08/30/2017 08:00 0015 whatever
002 08/30/2017 08:10 0025 whatever
003 08/30/2017 08:20 0025 whatever
004 08/30/2017 08:30 0011 whatever
005 08/30/2017 08:40 0014 whatever
006 08/30/2017 08:50 0025 whatever
007 08/30/2017 09:00 0021 whatever
008 08/30/2017 09:10 0024 whatever
009 08/30/2017 09:20 0017 whatever
010 08/30/2017 09:30 0025 whatever
011 08/30/2017 09:40 0026 whatever
012 08/30/2017 09:50 0026 whatever
013 08/30/2017 10:00 0018 whatever
014 08/30/2017 10:10 0015 whatever
015 08/30/2017 10:20 0013 whatever
016 08/30/2017 10:30 0025 whatever
017 08/30/2017 10:40 0011 whatever
018 08/30/2017 10:50 0011 whatever
019 08/30/2017 11:00 0032 whatever
What I need is to select only the first record (based on date_time) from each customer_id. Like this:
table_id date_time customer_id other_fields
-------- ---------------- ----------- ------------
001 08/30/2017 08:00 0015 whatever
002 08/30/2017 08:10 0025 whatever
004 08/30/2017 08:30 0011 whatever
005 08/30/2017 08:40 0014 whatever
007 08/30/2017 09:00 0021 whatever
008 08/30/2017 09:10 0024 whatever
009 08/30/2017 09:20 0017 whatever
011 08/30/2017 09:40 0026 whatever
013 08/30/2017 10:00 0018 whatever
015 08/30/2017 10:20 0013 whatever
019 08/30/2017 11:00 0032 whatever
Regards,
Hernando.