WebSep 23, 2024 · In the above query, first we sort the rows by product (ascending) and order_date (descending). Then we use the DISTINCT ON clause to select only the top record per group, which is nothing but the last record per group. Bonus Read : How to Create Histogram in PostgreSQL. Hopefully, now you can easily get the last row per … Web1 Answer. select id, requestid, timestamp, message from logs inner join ( select min (id) as min_id , requestid from logs group by requestid ) t on t.min_id = logs.id and t.requestid = logs.requestid. Thanks. That worked. So did the partition answer in the post that was linked to in the comment to my first post.
PostgreSQL- Select first row in each GROUP BY group
WebFor the sake of completeness, here's another possible solution: SELECT sensorID,timestamp,sensorField1,sensorField2 FROM sensorTable s1 WHERE timestamp = (SELECT MAX (timestamp) FROM sensorTable s2 WHERE s1.sensorID = s2.sensorID) ORDER BY sensorID, timestamp; Pretty self-explaining I think, but here's more info if … WebJul 27, 2011 · 5. This solution can be used to get the TOP N most recent rows for each partition (in the example, N is 1 in the WHERE statement and partition is doc_id): SELECT T.doc_id, T.status, T.date_created FROM ( SELECT a.*, ROW_NUMBER () OVER (PARTITION BY doc_id ORDER BY date_created DESC) AS rnk FROM doc a ) T … install kodi on firestick 2023
sql server - SQL Left Join first match only - Stack Overflow
WebIn this example: The PARTITION BY clause divided rows by group id into three partitions specified by group id 1, 2, and 3.; The ORDER BY clause sorted products in each product group ( or partition) from low to high.; The RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING clause defined the frame starting from the first row … WebMay 1, 2014 · 2 Answers. Sorted by: 5. This can easily be solved using a window function (standard SQL) select user_id, action, date from ( select user_id, action, date, min (date) over (partition by user_id) as min_date from actions ) t where date = min_date order by user_id; Using window functions is most probably faster than a self join on the table. Web6 Answers. You should find out last timestamp values in each group (subquery), and then join this subquery to the table -. SELECT t1.*. FROM messages t1 JOIN (SELECT from_id, MAX (timestamp) timestamp FROM messages GROUP BY from_id) t2 ON t1.from_id = t2.from_id AND t1.timestamp = t2.timestamp; jim bowmer temple texas