title: How should I design my database for different user has different devices?
body: <p>I was confused about database design.</p>
  
  <p>This is my request: There are different users; a user can has one or more devices. Some users will have thousands devices even ten thousand devices. A device has many operation records. One day adds 10-20 operation records.</p>
  
  <p>I prepare to create a table for user record userId, passWord. A different user creates different device list table record deviceNum, devicState. A device has a operation table record operation records.</p>
  
  <p>So,  my database will have many many tables. I guess I have more one hundred thousand devices. Should I create one hundred thousand devices tables?</p>