What is the difference between Primary Key only and Primary Key constraint? -


i new sql , if question silly please forgive ignorance.

what difference between primary key , primary key constraint?

difference between this

create table customers(    id   int              not null,    primary key (id, name)

and this

create table customers(    id   int              not null,   constraint [pk_id_name] primary key (id, name)

thank you, dash

well, same (you have constraint in both cases), difference can give name constraint in second version.


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