This is personal study note Copyright and original reference: https://www.youtube.com/watch?v=vJNEVsnY8K4&list=PLuHgQVnccGMDF6rHsY9qMuJMd295Yk4sa ================================================================================ Before considering denormalization, consider followings - index (reading row becomes faster, writing becomes slower, larger consumption on the disk) - application side (for example, use cache) Then, consider denormalization