I have a doubt just want to clear it. Generally we tend to make some integer/decimal/numeric column as a primary index & have a tendency to avoid string columns as primary index.
Not sure abt the specific reason .. Please correct me if i am wrong.
Thanks in advance.
Integer literals take less space as compared to charater literals.
For example, INT takes 4 bytes and CHAR(10) would take 10 bytes .... which effectively means more data to store, retrieve and move around .... hence would have an impact on performance.