You can create a table with a Unique Primary Index (UPI), a Non-Unique Primary Index (NUPI), or No Primary Index (NoPI).
| IF you create a table with... | THEN... |
|---|---|
| a NUPI | the PI is a column, or columns, that may have duplicate values. |
| a UPI | the PI is a column, or columns, that has no duplicate values. |
| NoPI | there is no PI column and rows are not hashed based on any column values. |