目录一.数据库的内嵌函数1.1聚合函数COUNT([DISTINCT] expr)SUM([DISTINCT] expr)AVG([DISTINCT] expr)MAX([DISTINCT] expr)MIN([DISTINCT] expr)1.2日期函数1.3字符串处理函数1.4 数学函数1.5其他常用的函数二.联合
I have an error ? My pl/Sql Developer says my oracle database cannot find the service descriptor But when I Do a check the listener I get this error.