You could also ssh into your DH account and type:
mysqldump -uOLDUSERNAME -pOLDPASSWORD -h OLDMYSQLSERVER OLDDATABASENAME > LOCALDUMP.sql
However, the old MySQL has to support external connections. Then you create a Database, a User, Password and Hostname at DH (using the panel) and enter the following, after the command above has run:
mysql -u DHUSERNAME -p DHPASSWORD -h DHMYSQLSERVER < LOCALDUMP.sql
This will locally import the Database to DH.
You have to replace all the capitalized words above with your data.
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