I was thinking of formatting it like this

TYYYYMMDDNNNN (2 character + 12 digits)

Where

T is character (TR or SL) YYYY is year (2018) MM is month (03) DD is day (30) N is sequential number (0001, 0002, 0003 etc.)

I need auto increment N after getting last data from mysql database.

Such as

20180330-0001, 20180330-0002, 20180330-0003.

20180331-0001, 20180331-0002.

20180401-0001, 20180401-0002, 20180401-0003 etc.