Paul,
Do you know if there is any performance differences between a
unique index and primary key (if there are no nulls)?
Is the index file format the same as the primary key?
Brent
At 05:09 PM 4/5/2002, you wrote:
>>Here are a few easy philosophical questions for a change:
>>
>>1) For performance or storage benefits, is there a difference between a
>>Unique Index and Primary Key?
>
>There can be only one primary key. There can be multiple unique indexes.
>
>Primary keys cannot contain NULL values. Unique indexes can allow NULL
>values (and in fact, NULL is the one value that can occur multiple
>times in a unique index).
>
>>
>>2) Is there a reason why I should use Primary Key instead of a Unique Index?
>>
>>3) Why isn't there a syntax for "create primary index index_name on
>>table_name (fieldlist)" ? I know a primary key can be added with "Alter
>>table", but if I'm defining indexes for a table, it would look a lot better
>>in the script if I was using the same syntax.
>>
>>TIA
>>
>>Brent
>>
>>sql, query
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