just create the portal-ext.properties in your 3. liferay-portal\tomcat-x.x.xx\webapps\ROOT\WEB-INF\classes
and add these properties there after creating a database in sql
1jdbc.default.driverClassName=com.mysql.jdbc.Driver
2 jdbc.default.url=jdbc:mysql://localhost/lportal?useUnicode=true&characterEncoding=UTF-8&useFastDateParsing=false
3 jdbc.default.username=
4 jdbc.default.password=
you dont need to use my sql through eclipse