just wondering what is the performance difference between:
PRIMARY KEY [/|index_type|/] (/|index_col_name|/1,/|index_col_name|/2)
at the time of the table creation
create index index_name1 on table_name (/|index_col_name|/1);
create index index_name2 on table_name (/|index_col_name|/2);
after the table has been made?
the question i guess is:
is there performance advantage to have a primary key defined on two (or more) fields
(columns) at the time of table creation or
is it better to have different indexes (keys) defined separately for each column that
needs to be indexed?