gallery (4 in a row) // carefull newbie

Hi all I am making a gallery for my Homepage. Now, I want to make little tumbnails of my work and make a table out of them. So, to not put them all in a row, what whould make the site unreadable, i have to put them in a little table, an i think 4 in each row would be ok. I like to read out the pic's name etc. out of a mysql table. But how do make the script to write a </tr> after it read out 4 entries of a mysql table? Thanks in advance :)