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Date: Thu, 5 Feb 2026 12:32:03 +0100
From: Thiemo Kellner <thiemo@gelassene-pferde.biz>
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Subject: Re: Top -N Query performance issue and high CPU usage
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A nested loop is not bad per se, at least in Oracle. It depends on the data. If the number of rows participating in the join table are very unequal, the NL is the more efficient join. I would presume that every join of a fact table with a dimension table belongs to that category.

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  <span dir="ltr" style="margin-top:0; margin-bottom:0;">A nested loop is not bad per se, at least in Oracle. It depends on the data. If the number of rows participating in the join table are very unequal, the NL is the more efficient join. I would presume that every join of a fact table with a dimension table belongs to that category.</span>
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