title: BIGINT mysql performance compared to INT
body: <p>I'm trying to find out if my table will get less performant if I change the primary key to BIGINT(20). At the moment, I'm using INT(7) and have about <strong>300.000 entries already with large IDs (7 or 8 digits)</strong>.
  I searched a lot already but only found out that it uses more disk-space (which is obvious). </p>
  
  <p>All of my IDs have 7 digits right now, but my customer wants to change to 8 digits. I won't be able to easily change the software in the future, so I thought about using BIGINT(20) now just in case. Would it be less performant if I use BIGINT even though I don't need to yet?</p>
  
  <p>Does anyone with experience doing this have suggestions regarding speed and performance?</p>