What does an Index mean to a Query
This post is about the importance of a right index to a query. The following simple query was considered.
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SELECT [GroupBy1].[A1] AS [C1] FROM ( SELECT MAX([Extent1].[CreatedDate]) AS [A1] FROM [dbo].[GeoIP2Location] AS [Extent1] WITH (NOLOCK) ) AS [GroupBy1] |
Even simple, this query was causing troubles on our production systems. The query is generated from .NET Entity Framework. A simple Continue reading What does an Index mean to a Query