what is the Proferance issue if i create non clusterd index without clusterd index?

Hi All,

I have very big table where we have 40000000 records. but don't have any Primary key  so i cannot create clusters index. i have integer type columns in this table but not unique data.

please suggest me how i have improve performance of my query, without clustered index

Please help.

Thanks!

I didn't find the right solution from the Internet.

References:

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/44ac640f-ca09-4f27-967f-f5c470c6189e/what-is-the-proferance-issue-if-i-create-non-clusterd-index-without-clusterd-index?forum=sqldatabaseengine

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