逻辑读是如何计算的？
我已经阅读了逻辑读取的定义：
http://msdn.microsoft .com/en-us/library/ms184361.aspx
它说：
“从数据缓存读取的页数。”
我有两个表（table_1 的行数为 141，table_2 的行数为 16.811），当我运行这两个查询时，它给出以下结果。
SELECT * FROM Table_1
results
Scan count 1, logical reads 6, physical reads 0, read-ahead reads 0.
SELECT * FROM Table_2
results
scan count 1, logical reads 701, physical reads 0, read-ahead reads 0
如果逻辑读取是“从数据缓存读取的页数”。那么什么是页面呢？它是如何计算的？
I've read the definition of logical reads from:
http://msdn.microsoft.com/en-us/library/ms184361.aspx
it says:
"Number of pages read from the data cache."
I have two tables (Row count of table_1 is 141, and table_2 is 16.811), when I run those two queries, it gives the following result.
SELECT * FROM Table_1
results
Scan count 1, logical reads 6, physical reads 0, read-ahead reads 0.
SELECT * FROM Table_2
results
scan count 1, logical reads 701, physical reads 0, read-ahead reads 0
if logic reads is "Number of pages read from the data cache." then what is a page ? How it is calculated ?
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页是
SQL Server使用的最小物理数据单元。一个页
8K长，可能包含多个表记录、索引记录和其他信息。即使一行有
10字节长，也需要读取整个页面。在您的例子中，一个页面平均包含大约
20行。A page is a minimal physical data unit
SQL Serverworks with.A page is
8Klong and may contain several table records, index records and other information.Even if a row is
10bytes long, the whole page needs to be read.In your case, a page contains about
20rows in average.