Query Get Max And Min With Two Situation Same And Different Date

[newphpcoder]

Hi..I know its a couple of weeks that i have problem in datetime..For example i have this data:00100 2011-11-20 05:35:0000100 2011-11-20 13:35:0000100 2011-11-21 21:35:0000100 2011-11-22 05:35:00when I tried this query for testing:

SELECT a.EMP_NO, max(a.DTR), min(b.DTR) FROM regular_dtr a LEFT JOIN regular_dtr b ON a.EMP_NO = b.EMP_NO;

i have this output:EMP_NO--max_dtr------------------min_dtr00100----2011-11-22 05:35:00-----2011-11-20 05:35:00i need result is:EMP_NO--max_dtr------------------min_dtr00100----2011-11-20 13:35:00-----2011-11-20 05:35:0000100----2011-11-22 05:35:00-----2011-11-21 21:35:00I really, don't know what syntax should i need..I'm sorry if until now, I did not solve this:(Any help is highly appreciated..Thank you so much...i hope you would not angry with me...the reason why i post again this problem because now i only have two columns, EMP_NO and DTR(IN and OUT) and i have no right to demand to separate the data of in and out...so that in my part I need to do that but sad to say, I have only few knowledge in mysql..specially in functions.

[justsomeguy]

I don't think you can get a result like that in SQL, it's not clear to the database which dates are supposed to match with each other with a structure like that. If you can't change the table structure then you'll need to get all of the data and process it with another language.