sql server - Include additional columns in a non clustered primary key index -


i have defined primary key on table nonclustered. non-clustered indexes explicitly created create nonclustered index possible include additional (non-indexed) columns. same possible implicitly created primary key non-clustered index?

the syntax include columns available create nonclustered index, specifically

include (column [ ,... n ] ) specifies non-key columns added leaf level of nonclustered index. nonclustered index can unique or non-unique.

is not available add constraint, cannot include columns primary key, if non-clustered.

a primary key useful unique identifier record, , candidate key available referential constraints. however, performance reasons, if have clustering key on column , have no other candidate keys promote pk, can create additional non-clustered index on primary key column(s) , include other columns onto index.


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