在整个开发过程中,sql查询操作的频率比较高,在不同的业务场景下会出现不同的查询需求,以下是我在项目中遇到的查询需求,总结一下. [查询一]:取查询出的第一条数据 select * from (select * from [tableName] order by [key] asc/desc ) where rownum = 1 [查询二]:查询数值数据时,小于0的数值,小数点前的0需要显示 Oracle中对于数值的数据,小于0时小数点前的0不显示,如:.9,实际查询操作中需要显示为…
Oracle中有三类进程: 1 User Process 2 Server Process Server Process is a program that directly interacts with the Oracle Server. Once a user has established a connection, a server is started to handle the user processes requests. The user process does not i…