MySQL Select Group of Records Based on latest timestamp

Question

I have a routine that runs every few hours that creates several entries in a table used for logging. What I need to do is select all the records with the most recent

Answer 1

Assuming you mean multiple entries in your Table_Logs table could have the same timestamp and you want to return each of those that were entered most recently, you need to use GROUP BY:

SELECT Field1, Field2, Max(TimeStamp) maxTime
FROM Table_Logs
WHERE Account_Id = '12345'
GROUP BY Field1, Field2

Field1, etc. are the fields you want to return in Table_Logs.

Here is some sample SQL Fiddle to try out.

Good luck.

Answer 2

I think what you want is to group by the timestamp. Assuming that all the ones entered at 10am had the same timestamp, and 2 pm, ditto, would be something like:

  SELECT timestamp, Field1, Field2
    FROM Table_Logs
GROUP BY timestamp

If your timestamps are too precise, simply do a substring:

  SELECT LEFT(timestamp, 5), Field1, Field2
    FROM Table_Logs
GROUP BY LEFT(timestamp, 5)

Assuming the timestamp is a string (log file). If not, you have to stringify it.