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you don't actually need to worry much as there are some scripts which you can perform on your PC which can take out the password from .dat file.
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Its not as easy as you might think.
Lets say you have a good randomly generated password with 6 alphanumerical symbols [a-z,A-Z,0-9] and remember nothing about it. Thats 8
62 possible combinations. With 1600 passwords checked per second (its roughly what my GPU does on bitcoin core wallet files) it would take 1.9*10
45 years to crack the password. Testing a few million passwords is no problem though, but you will have to remember a lot about your password to get there.