Database File Size Getting Larger From Search Query

I'm having a problem with my database filesize getting larger with the more searches i do. At first i couldn't figure out how it was getting so big, but then i tried a few things and came to the conclusion that every time i do a search it increases its filezile.

what made me notice this at first is that the file size of the original copy of my db is 13MB, but if i Save As a different name, like Assets_Backup, then the size of the new file is only 2MB, and after i do some searches it increases again.

here is a file with just my search form and search query so you can see the code for them. i removed everything else to shrink the file down, which also made the search form not function properly, but i thought the design and code might be enough.

is there something that i can change to keep it from remembering every search?

thanks for any help.

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after searching the topic a bit more i've found that compacting the database will shrink it down to 2MB, but is this something that will have to be done on a regular basis, or is there a way for it to do it on its own?