fastest way to deduplicate a list

fastest way to deduplicate a list

am 21.10.2007 06:10:37 von Michael Evanchik

Im trying to dedupe a table with only one field on it. The table has
40 million records in it. What is the fastest way?

1) create a table with a unque constraint on it insert into that
table?

2) create a table without a unique constraint on it and use insert
into table select distinct un from table2?

3) another way?

Michael

Re: fastest way to deduplicate a list

am 21.10.2007 11:10:12 von Erland Sommarskog

Michael Evanchik (mre224@yahoo.com) writes:
> Im trying to dedupe a table with only one field on it. The table has
> 40 million records in it. What is the fastest way?
>
> 1) create a table with a unque constraint on it insert into that
> table?

I assume that you would use the IGNORE_DUP_KEY option? Else the scheme
wouldn't work. That could very well be the fastest method.



--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

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