11 2013 档案
摘要:Tuning MethodologyWhen dealing with performance problems, database professionals tend to focus on the technical aspects of the system, such as resource queues, resource utilization, and so on. However, users perceive performance problems simply as waitsthey make a request and have to wait to get the
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摘要:Summary DescriptionThe SQL language is spoken by most database experts, and all relational database products include some dialect of the SQL standard. Nevertheless, each product has its own particular query-processing mechanism. Understanding the way a database engine processes queries helps softwar
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摘要:Logical Query Processing Phases Summary(8) SELECT (9) DISTINCT (11) (1) FROM (3) JOIN (2) ON (4) WHERE (5) GROUP BY (6) WITH {CUBE | ROLLUP}(7) HAVING (10) ORDER BY Brief Description of Logical Query Processing Phases Don't worry too much if the description of the steps doesn't seem ...
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