Finding averages timestamp based on two rows

Question

Basically i'm attempting to get an average based on two time stamps inside a database, let's say for example i have a product, I insert it into the database 10 times with an listed_time and a sell_time, I want to group all 10 rows together and find the average between both the listed_time and the sell_time to find on average on how long it took to sell.

EDIT : timestamps are inserted as time() not date()

The code in which i tried and failed to work was

$query = $db->runSQL("SELECT AVG(TIMESTAMPDIFF(SECOND, listed_time, sell_time)) from trade");
while($row = mysql_fetch_assoc($query)) {
    echo $row['AVG(TIMESTAMPDIFF(SECOND, listed_time, sell_time))']."</br>";
}

Possible duplicate: [How to find the average time difference between rows in a table](http://stackoverflow.com/questions/876842/how-to-find-the-average-time-difference-between-rows-in-a-table) — nickhar, Apr 18 '13 at 14:13

Stephan · Accepted Answer · 2013-04-18T16:25:42.613

2

You can try this for that 10 rows:

SELECT AVG(TIMESTAMPDIFF(SECOND, listed_time, sell_time ) ) as za_avg ...

This will give you the average time (for those 10 rows) it took to sell the items

edited Apr 18 '13 at 16:25

answered Apr 18 '13 at 14:23

Stephan

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can you pls tell me why it failed? was there a error? or the output wasn't the one desired? – Stephan Apr 18 '13 at 14:41
i have added the code i used to my initial question, it didn't echo anything – Curtis Crewe Apr 18 '13 at 14:48
I've added an alias so try `echo $row['za_avg']."";` and see what the output is – Stephan Apr 18 '13 at 16:26

Finding averages timestamp based on two rows

1 Answers1