I realised that some data from my simple mysql+php website has be deleted from this IP address: 204.236.226.210 and from 174.129.228.67. That i realised from access.log.current file where stated

"GET /robots.txt HTTP/1.0" 404 2302 www.mywebsite.de "-" "ia_archiver (+http://www.alexa.com/site/help/webmasters; crawler@alexa.co"

Can some body help me how i can secure my database? I have been changing passwords but no way. Its now 5th time

Please write down some tips...

Regards, bye.

it seems that your php website could have GET requests which are sql sensitive. If so, then change them to "Post" requests. Changing password of db will not help as the connection from your website to DB will be used for hacking.

all the best!

This can be the result of different attacks that are possible these days, XSS injection, SQL injection, frame injection are few to name.

Your case seems more like sql injection, go through the details on wikipedia. There are some prevention techniques as well.

If you believe somebody has really hacked your website/server then whatever you do, in the end your hosting provider can help you a lot more than others.