isladogs
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I have a very large Access datafile of UK postcodes which serves as one of the backend databases for my UK Postal Address Finder database which I'm about to release via my website (finally!!)
NOTE:
The installer file for the website includes this large file & several other much smaller files.
It compresses all files whilst creating a single EXE file
My first attempt in this case resulted in an EXE file of about 1.4GB
Removing the password, the EXE size dropped to 127MB
So I tested using Winzip
Approx file size before compression 1.262GB
After compression using WinZip, approx file sixe = 116.1MB (<10% of original)
All good so far
However, I then decided to password protect the datafile.
Negligible change in file size as you would expect
However, the zipped version became 1.2622GB - slightly bigger than the original file.
Using zipx format made little difference.
In other words ... useless for compression
Can anyone explain why 'encrypting' an Access DB with a password causes this effect.
@DocMan: Thanks in advance for your explanation.
My guess is that password protection prevents Winzip doing any compression & that the size increase is just the result of its file scan
NOTE:
The installer file for the website includes this large file & several other much smaller files.
It compresses all files whilst creating a single EXE file
My first attempt in this case resulted in an EXE file of about 1.4GB
Removing the password, the EXE size dropped to 127MB
So I tested using Winzip
Approx file size before compression 1.262GB
After compression using WinZip, approx file sixe = 116.1MB (<10% of original)
All good so far
However, I then decided to password protect the datafile.
Negligible change in file size as you would expect
However, the zipped version became 1.2622GB - slightly bigger than the original file.
Using zipx format made little difference.
In other words ... useless for compression
Can anyone explain why 'encrypting' an Access DB with a password causes this effect.
@DocMan: Thanks in advance for your explanation.
My guess is that password protection prevents Winzip doing any compression & that the size increase is just the result of its file scan
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