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Question

I am importing data from an access table to SQL. I have a primary key is SQL "quoteID" which obviously doesn't allow duplicates but I'm looking to add that requirement to another field.

Can't seem to find where to set that? perhaps it has to do with the field type??

Answer 1

You can require that a column be unique using a unique constraint or unique index:

alter table t add constraint unq_t_col unique (col);

or:

create unique index unq_t_col on t(col);

Answer 2

Make the field a primary key of the table. Or put an index on that field that enforces unique values.