I'm wondering the differences or comparisons of having an Auto Increment int Id column or an indexed VARCHAR(32) column. Which one would be faster if I had a second table that references the first table by joining? Like in the second table, would I store the Auto Increment INT id or the indexed VARCHAR column? What are the advantages or disadvantages, if any?
Which would be the more common practice? Create Auto Increment id column for almost every table? Or we can simply index a column that has a unique 36-char ID (like in SugarCRM) so the other tables can just use that when doing joins? I hope I explained my question fairly clear.