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Mysql Oracle Sql server 三种数据库默认端口
** SQL Server默认端口号为：1433
URL:"jdbc:microsoft:SQL Server://localhost:1433; drivername:“com.microsoft.jdbc.SQL Server.SQL ServerDriver”;
MySQL 默认端口号为：3306
URL:jdbc:MySQL://localhost:3306/数据库名?user=root&password=&useUnicode=true&characterEncoding=gbk drivername:“com.MySQL.jdbc.Driver”;
Oracle 默认端口号为：1521
URL:"jdbc:Oracle:thin:@localhost:1521:orcl "; drivername:"Oracle.jdbc.driver.OracleDriver
