Why does the query optimizer use decimals for estimated number of rows?
Question
I'm analyzing a bad performing query. I've looked for an Index Seek node which is generating a high IO. I'm assuming this is due to usage of low cardinality index, because estimated number of rows is far from the actual number of returned rows. My question is why the Query Optimizer shows the estimated number of rows in decimal notation such as 2216,86 ?
1 answers
solution1
0 2014-03-02 14:52:41
因为可能它内部使用了浮点数进行所有计算？
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