Oracle索引
oracle的索引陷阱一个表中有几百万条数据,对某个字段加了索引,但是查询时性能并没有什么提高,这主要可能是oracle的索引限制造成的。 oracle的索引有一些索引限制,在这些索引限制发生的情况下,即使已经加了索引,oracle还是会执行一次全表扫描,查询的性能不会比不加索引有所提高,反而...
Javascript Drag&Drop Example
Code Example: Drag Object (compatible with IE, Firefox, Opera...) .dragAble {position:relative;cursor:move;}
Hibernate session management
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