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Don,
I agree with you about all the ineffiencies of using one file
per company. But for better or worse when you use one file per
company you are better protected from database corruption. This
is a problem that happens more often than people think. Even
Microsoft Access spends a good full page in their manual explaining
how to protect from them. In other words, unless you have a good backup
of your data, your whole database will be useless. But if you want your
program to scan thousands of companies very fast you still have to
put all data in one database. We are taking this latter approach
in our upcoming StockWiz for Windows 95. We made a name for ourselves
for being very fast and we need to put speed ahead of convenience.
Also the easiest way to find out how much space is wasted by a file
is to write down the number of available bytes on your drive, create
a new file that only has a few bytes and then count the free bytes
again.
--Steve
At 07:45 AM 7/3/97 -0400, DanMartinz@xxxxxxx wrote:
>StockWiz support,
>thank you for your response. The first disk compression program I purchased
>was Stacker 4.0 3 years ago. At the time it was state of the art and worked
>with DOS and Windows 3.1. When I upgraded to Windows 95 in January I had to
>research this subject and found the state of the art today is DriveSpace 3.
> DriveSpace 3 is included in the MicroSoft Plus! package ($50). DriveSpace 3
>is the only 32 bit, Pentium-optimized, Windows 95 program on the market. It
>is 20% faster than the DriveSpace included free in Windows 95. DriveSpace 3
>also allows you to create Compressed Volume Files (CVF's) up to 2 GB's versus
>only a puny 512 MB for DriveSpace. I do not use Windows 3.1 anymore but I
>never had any problems with Stacker 4.0. I have not any problems with
>DriveSpace 3. With my Cyrix P150 I have not noticed any speed problems
>attributable to DS3. The CPU's made today are at least 20% faster.
>
>A sector is always 512 bytes. A common mistake people make is they mistake
>clusters for sectors. The larger the clusters, the more sectors per cluster.
> In uncompressed hard drives, the size of the clusters vary with the size of
>the drive. This is because the number of clusters DOS and Windows 95 can
>allocate is 64K. After rereading the drive table in my Partition Magic
>manual, I can tell you 24K is not a valid cluster size.
>
>Drive Size MB Cluster size Ave. wasted space
>128 - 255 4KB 4%
>256 - 511 8KB 10%
>512 - 1,023 16KB 25%
>1,024 - 2,047 32KB 40%
>2,048 - 4,096 64KB 50%
>
>Most people buy drives larger than 1 GB and are unknowingly wasting 40% of
>their disk space. The only way you can reduce this waste is to make the
>drive's partitions smaller than 512 MB. DS3 stores data in 32K blocks
>however data can be stored in nonsequential sectors. This means a file can
>be broken up, if necessary, into different sectors on the drive and produces
>very little waste. With DS3 I can create any size partitions I want with
>multiple DS3 CVF's up to 2 GB in size. There is no waste because the data is
>stored inside the CVF's. This not only stops the above waste but also
>compresses the data, a twofold advantage.
>
>I agree MetaStock 6 has a very inefficient way of storing data. Even buggy
>Window on Wall Street Pro v5 is better and faster. However, in my humble
>opinion, MetaStock 6 is the best end-of-day technical analysis program for
>under $1000. Right now, I am leaning towards using Quote.Com. While I have
>to do everything manually using the Equis DownLoader for ASCII files, I would
>only have one database and they only cost $10/mo. I will look over your
>product and data service again before I decide what to buy. If necessary, I
>will replace my 1.6 GB drive with a larger one. By the way, this 1.6 GB is
>EIGHT TIMES larger than the drive I had for Windows 3.1.
>
>Daniel.
>
>
>In a message dated 97-07-02 17:29:05 EDT, you write:
>
><< t is not that complicated when you really think about it. Using
> compression on your hard disk would not help much. The problem
> is that every file takes at least 24K (even if the size is 1 byte).
> Compression software cuts the sector size down to 12K. This still
> wastes a lot of space when you have 12,000 files. This is why we
> have one database and not 12,000 files. Metastock started out as
> a charting program and not a screening program. Efficient storage
> was not a priority for them. We simply refuse to lower our standards
> so we can meet theirs. This is why you need to have two databases.
>
> We also make it easy to apply split factors from files we supply.
> So, when you export to Metastock files the data are already adjusted.
>
> We will be releasing soon our Windows 95 version that makes things
> even easier. Stay tuned...
>
>
> StockWiz support
>
> At 08:19 PM 7/1/97 -0400, you wrote:
> >I will be buying the Investor's Reference Library CD-ROM stock price
>database
> >which uses the old 256 files per directory format. It has 5 years of data.
> > The new MetaStock v6 directory format is not an issue here.
> >
> >I have MetaStock v6. Every single information provider on the Net makes
>you
> >maintain their database IN ADDITION TO METASTOCK'S. I have a 1.6 GB drive
> >with Microsoft's DriveSpace 3 compression software. I thought I had plenty
> >of room. Now I find I will barely be able to squeeze all the data I want
> >because of this duplication. I don't need a second database! The CD-ROM I
> >get with MetaStock has 5 years of data. I can get others with even more.
> > Why would I need a second and smaller 2 mos database maintained daily?
> >
> >Also, many stock price info providers make you MANUALLY go in and change
> >stock splits and ticker name changes. If I maintained all US stocks, I
>would
> >have to change 15 per day! Instead of wasting time and effort creating a
> >technical analysis program, stock price info providers should concentrate
>on
> >information and conversion to other technical analysis program databases
> >only. You can now get a cheap TA program for $50. These TA programs are
> >Windows 95 based and always better than the programs supplied by info
> >providers. They specialize in this field. The only way I can have
> >everything done automatically is if I use MetaStock's Reuters service.
> They
> >want $35/month. There is no way I am going to pay $35/month for just US
> >Stocks end-of-day!
> >
> >Why is this so complicated???!!
> >>
>
>
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