I have 3 tables, 'u' 'd' 's'

'u' has

• userid
  
• divid

'd' has

• divid
  
• divname
  

's' has

• sname
  
• primaryuserid
  
• secondaryuserid

Now what I'd like to do is display a table with rows of the following format

• userid, divname, sname

Plus figure out a way to decipher whether userid is a primary or secondary for this sname table.

I'm able to show userid and divname using a left join, but I don't know how I would add a third table? To make it trickier, there can be more than 1 snames for each userid, up to ~20. Is there a way to display 0-20 snames depending on the userid, seperated with commas?