SQL & PL/SQL

Hi Team,

I have below data in table.

col1       priority

x1               1

x2               2

x3               3

x4               4

if user update the priority column, then accordingly other value should change. for example. if user changes priority of x3 to 1, then output should be below.

col1       priority

x3               1

x1               2

x2               3

x4               4

how to achieve this ?

Balaji