I am just wondering that what are the differences between the following?
create table test(
person_id number
name varchar2(50),
surname varchar2(50)
);
create index my_indx on test(name);
create index my_indx2 on test(surname);
OR
create index my_indx3 on test(name, surname);
OR
create index my_indx4 on test(surname, name);
What are the differences among these three indexes?
When I create name and surname columns in same index (composite index) in order to index scan should I use both of them in the where clause?
My last question is, Is the order important for composite indexes?
Thanks in advance.