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Message Posted: Tue, 29 Nov 2005 @ 19:59:59 GMT

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The advantage of a MULTISET table is it eliminates the duplicate row check. This can save a considerable amount of time. For NUPI's that have the same key value, the chaining through the rows checking each column is eliminated. Chaining through the values is checking all the columns of the second row with all the columns of the first row. The third row is then read and needs to check all the columns for rows 1 & 2. You can see how performance will begin to slow down as the number of rows increase.

The disadvantage of a MULTISET table is that it allows duplicates, so if you do not want duplicates, a process will need to filter them out.

Most of our tables are MULTISET and we have not had many problems with them.

Hope this helps.

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