If a table column has is UNIQUE and has NOT NULL, is it
equivalent to a PRIMARY KEY column?

Answer Posted / dibya tara shakya

It will same but in case of primary key we can create the
master child relationship with other child table as foreign
key but in case of unique and not null we cannot.

another major difference is that Primary key constraint
applied Cluster index on that
column and unique key constraint non clustered index on
that column.

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