want to download 3GB database table from my development mysql server I need to download database structure with data. Total size of the DB is more than 3GB. If i use phpmyadmin it is not working. I have also tried by increasing the execution time in php.ini. I need some tool to import and Export the data base. My database server is Mysql server.

My requirement is any tool that will help to download Large database and Upload to another server. It should hold the download when internet fails. IF internet is ready it should continue the download process.

The answer already existing haven't worked for me. My issue is I need to export and import data from one server to other. if Internet Connection fails. It should not start a fresh export. It should continue the incomplete process.
The simple answer is "use the command line tools", these will run until complete assuming you have enough disk space, to produce the backup then draw that down to where you want it (if not the same server) via HTPS, SFTP, or similar. 

The other option of course, unless you need up-to-the-minute data, is to take a copy of the latest backup. If you don't have regular backups already then look into implementing them otherwise you are setting yourself up for a potential world of hurt later.

For more detailed/specific answer you'll need to update your question to describe you environment and what you have tried so far in more detail. Is this your own server or VM, a work machine you have limited access to, a shared host, ...? Linux/Windows/other? What actually happened on your attempts other than "didn't work"? A long delay then nothing, a long delay then an error message, an error message quickly, a fire is produced but is empty or incomplete, ...? If an error message: what was the text of that message?