SQLSERVER聚集索引和主键的误区
SQLSERVER聚集索引和主键的误区 很多人会把Primary Key和聚集索引搞混起来，或者认为这是同一个东西。这个概念是非常错误的。 主键是一个约束（constraint），他依附在一个索引上，这个索引可以是聚集索引，也可以是非聚集索引。 所以在一个（或一组）字段上
SQLSERVER聚集索引和主键的误区
很多人会把Primary Key和聚集索引搞混起来，或者认为这是同一个东西。这个概念是非常错误的。
主键是一个约束（constraint），他依附在一个索引上，这个索引可以是聚集索引，也可以是非聚集索引。
所以在一个（或一组）字段上有主键，服务器空间，只能说明他上面有个索引，服务器空间，虚拟主机，但不一定就是聚集索引。
例如下面：
#tempPKCL 4 ( ) #tempPKNCL 13 ( )
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