How many binary downloads can SQL Server handle?

Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
download it.. can SQL Server handle that?
It's on a dedicated machine, just one server, no load balancing and such.
Hi
It is not clear why you would want to hold such large binary files within
the database. The most likely bottleneck will be your network especially if
you only have one NIC.
John
"the friendly display name" wrote:

> Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
> download it.. can SQL Server handle that?
> It's on a dedicated machine, just one server, no load balancing and such.
|||It's not in our office, we're hosting externaly. So the network isn't the
problem.
Why are we doing it:
We offer files (self-made programs), the customer needs to be authorized to
be able to download them. We're offering currently over 20 files, each file
is in a certain group.. the customer can be in group 1, group 2, group 3...
and he can only download files, which are in the same group as him.
How to make that just with IIS? OK, forms auth., but you can only lock
certain folders, not files, and you can't do it programmaticaly, just with
web.config.
To offer them over the SQL Server.. I think it's the easiest way. If you
know better ways to do that, I'll listen.
"John Bell" wrote:
[vbcol=seagreen]
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially if
> you only have one NIC.
> John
> "the friendly display name" wrote:
|||Well, is SQL Server able to handle so many downloads with such configuration?
"John Bell" wrote:
[vbcol=seagreen]
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially if
> you only have one NIC.
> John
> "the friendly display name" wrote:
|||Hi
It could, but you will have to do your own benchmark on your own servers to
see if your configuration is up to it. Your solution will not be as scalable
as one that only stores pointers in the database and restricting access via
what they can retrieve.
John
"the friendly display name" wrote:
[vbcol=seagreen]
> Well, is SQL Server able to handle so many downloads with such configuration?
> "John Bell" wrote:

How many binary downloads can SQL Server handle?

Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
download it.. can SQL Server handle that?
It's on a dedicated machine, just one server, no load balancing and such.Hi
It is not clear why you would want to hold such large binary files within
the database. The most likely bottleneck will be your network especially if
you only have one NIC.
John
"the friendly display name" wrote:

> Let's asume we saved a 40 MB file in SQL Server, and 100 people at once wi
ll
> download it.. can SQL Server handle that?
> It's on a dedicated machine, just one server, no load balancing and such.|||It's not in our office, we're hosting externaly. So the network isn't the
problem.
Why are we doing it:
We offer files (self-made programs), the customer needs to be authorized to
be able to download them. We're offering currently over 20 files, each file
is in a certain group.. the customer can be in group 1, group 2, group 3...
and he can only download files, which are in the same group as him.
How to make that just with IIS? OK, forms auth., but you can only lock
certain folders, not files, and you can't do it programmaticaly, just with
web.config.
To offer them over the SQL Server.. I think it's the easiest way. If you
know better ways to do that, I'll listen.
"John Bell" wrote:
[vbcol=seagreen]
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially i
f
> you only have one NIC.
> John
> "the friendly display name" wrote:
>|||Well, is SQL Server able to handle so many downloads with such configuration
?
"John Bell" wrote:
[vbcol=seagreen]
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially i
f
> you only have one NIC.
> John
> "the friendly display name" wrote:
>|||Hi
It could, but you will have to do your own benchmark on your own servers to
see if your configuration is up to it. Your solution will not be as scalable
as one that only stores pointers in the database and restricting access via
what they can retrieve.
John
"the friendly display name" wrote:
[vbcol=seagreen]
> Well, is SQL Server able to handle so many downloads with such configurati
on?
> "John Bell" wrote:
>

How many binary downloads can SQL Server handle?

Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
download it.. can SQL Server handle that?
It's on a dedicated machine, just one server, no load balancing and such.
Hi
It is not clear why you would want to hold such large binary files within
the database. The most likely bottleneck will be your network especially if
you only have one NIC.
John
"the friendly display name" wrote:

> Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
> download it.. can SQL Server handle that?
> It's on a dedicated machine, just one server, no load balancing and such.
|||It's not in our office, we're hosting externaly. So the network isn't the
problem.
Why are we doing it:
We offer files (self-made programs), the customer needs to be authorized to
be able to download them. We're offering currently over 20 files, each file
is in a certain group.. the customer can be in group 1, group 2, group 3...
and he can only download files, which are in the same group as him.
How to make that just with IIS? OK, forms auth., but you can only lock
certain folders, not files, and you can't do it programmaticaly, just with
web.config.
To offer them over the SQL Server.. I think it's the easiest way. If you
know better ways to do that, I'll listen.
"John Bell" wrote:
[vbcol=seagreen]
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially if
> you only have one NIC.
> John
> "the friendly display name" wrote:
|||Well, is SQL Server able to handle so many downloads with such configuration?
"John Bell" wrote:
[vbcol=seagreen]
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially if
> you only have one NIC.
> John
> "the friendly display name" wrote:
|||Hi
It could, but you will have to do your own benchmark on your own servers to
see if your configuration is up to it. Your solution will not be as scalable
as one that only stores pointers in the database and restricting access via
what they can retrieve.
John
"the friendly display name" wrote:
[vbcol=seagreen]
> Well, is SQL Server able to handle so many downloads with such configuration?
> "John Bell" wrote:

How many binary downloads can SQL Server handle?

Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
download it.. can SQL Server handle that?
It's on a dedicated machine, just one server, no load balancing and such.Hi
It is not clear why you would want to hold such large binary files within
the database. The most likely bottleneck will be your network especially if
you only have one NIC.
John
"the friendly display name" wrote:
> Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
> download it.. can SQL Server handle that?
> It's on a dedicated machine, just one server, no load balancing and such.|||It's not in our office, we're hosting externaly. So the network isn't the
problem.
Why are we doing it:
We offer files (self-made programs), the customer needs to be authorized to
be able to download them. We're offering currently over 20 files, each file
is in a certain group.. the customer can be in group 1, group 2, group 3...
and he can only download files, which are in the same group as him.
How to make that just with IIS? OK, forms auth., but you can only lock
certain folders, not files, and you can't do it programmaticaly, just with
web.config.
To offer them over the SQL Server.. I think it's the easiest way. If you
know better ways to do that, I'll listen.
"John Bell" wrote:
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially if
> you only have one NIC.
> John
> "the friendly display name" wrote:
> > Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
> > download it.. can SQL Server handle that?
> >
> > It's on a dedicated machine, just one server, no load balancing and such.|||Well, is SQL Server able to handle so many downloads with such configuration?
"John Bell" wrote:
> Hi
> It is not clear why you would want to hold such large binary files within
> the database. The most likely bottleneck will be your network especially if
> you only have one NIC.
> John
> "the friendly display name" wrote:
> > Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
> > download it.. can SQL Server handle that?
> >
> > It's on a dedicated machine, just one server, no load balancing and such.|||Hi
It could, but you will have to do your own benchmark on your own servers to
see if your configuration is up to it. Your solution will not be as scalable
as one that only stores pointers in the database and restricting access via
what they can retrieve.
John
"the friendly display name" wrote:
> Well, is SQL Server able to handle so many downloads with such configuration?
> "John Bell" wrote:
> > Hi
> >
> > It is not clear why you would want to hold such large binary files within
> > the database. The most likely bottleneck will be your network especially if
> > you only have one NIC.
> >
> > John
> >
> > "the friendly display name" wrote:
> >
> > > Let's asume we saved a 40 MB file in SQL Server, and 100 people at once will
> > > download it.. can SQL Server handle that?
> > >
> > > It's on a dedicated machine, just one server, no load balancing and such.

How is the 'Score' value derived in the Lift chart/Mining legend for Data Mining Models?

Hi,

I have just run a simple data set through a model to predict a simple true or false value (i.e. binary output)

The Lift Chart/Mining Legend in Analysis Services shows three results – Score, Population Correct (%), and Predict Probability (%)

Population Correct I beleive is the percentage of predictions it got right out of the total number of predictions it tried to make. Is this correct?

However, I can’t work out how the other two are derived in particular the 'SCORE'. To give a live example the scores were as follows:

Model Score Pop Correct Pred Probability

Decision Trees 0.83 76.59% 54.28%

Neural Network 0.75 67.63% 50.05%

Ideal Model 100.00%

Can anyone help with this and give a detailed explanation?

Many thanks,

S Rajput

Hi

The Predict Probability is the probability of the most popular prediction state for the model.

The Score is the log scatter score for a scatter plot of (x=Actual Value,y=Predicted Value) where each point has an associated probability. There are a lot of examples on the mathematical series for this calculation which you can look up.

Hope this helps.

Shuvro

|||

So does a larger score mean a better fit for the model? How is a scatter score calculated?

|||

Here're some more details about the scatter score calculation:

This score is the (geometric) mean score of all the points constituting the scatter plot.

Here is how it works.

0) Each point on a scatter plot corresponds to a test case and has the form (a,b(M)), where a is the actual attribute value for the case and b(M) is the value predicted using the model M;

1) First define the score(a,b(M)) for *one* individual scatter point; to do this compare the (a,b(M)) to the best prediction we can do without using any model; that prediction is of course marginalMean; so

score(a,b(M)) = likelihood ( b(M), given a, given M) / likelihood( marginalMean, given a)

2) Then average out all the scores across the entire scatter plot;

Technically is was simpler to average them out as

score = ( Product[ score(a,b) | forall (a,b) in the scatter plot])^(1/n), where n is the number of points in the scatter plot.

So that’s how it is currently done.

Details:

The statistical meaning of the individual point score is the predictive lift for the model M measured at that point. It is essentially the same notion as the Predict Likelihood fraction for the case contributed by the continuous attribute for which the scatter plot has been built.

The specific formula for this is score(a,b) = pdf( N(a, predictStdev), b) / pdf( N(a, marginalStdev), marginalMean)

where N(mu, sigma) is the normal distribution with mean of mu and Stdev sigma and

pdf(N(mu, sigma), x) is its probability density function described by exp((x-mu)^2/(2*sigma))/sqrt(2Pi)/sigma.

How is the 'Score' value derived in the Lift chart/Mining legend for Data Mining Model

Hi,

I have just run a simple data set through a model to predict a simple true or false value (i.e. binary output)

The Lift Chart/Mining Legend in Analysis Services shows three results – Score, Population Correct (%), and Predict Probability (%)

Population Correct I beleive is the percentage of predictions it got right out of the total number of predictions it tried to make. Is this correct?

However, I can’t work out how the other two are derived in particular the 'SCORE'. To give a live example the scores were as follows:

Model Score Pop Correct Pred Probability

Decision Trees 0.83 76.59% 54.28%

Neural Network 0.75 67.63% 50.05%

Ideal Model 100.00%

Can anyone help with this and give a detailed explanation?

Many thanks,

S Rajput

Hi

The Predict Probability is the probability of the most popular prediction state for the model.

The Score is the log scatter score for a scatter plot of (x=Actual Value,y=Predicted Value) where each point has an associated probability. There are a lot of examples on the mathematical series for this calculation which you can look up.

Hope this helps.

Shuvro

|||

So does a larger score mean a better fit for the model? How is a scatter score calculated?

|||

Here're some more details about the scatter score calculation:

This score is the (geometric) mean score of all the points constituting the scatter plot.

Here is how it works.

0) Each point on a scatter plot corresponds to a test case and has the form (a,b(M)), where a is the actual attribute value for the case and b(M) is the value predicted using the model M;

1) First define the score(a,b(M)) for *one* individual scatter point; to do this compare the (a,b(M)) to the best prediction we can do without using any model; that prediction is of course marginalMean; so

score(a,b(M)) = likelihood ( b(M), given a, given M) / likelihood( marginalMean, given a)

2) Then average out all the scores across the entire scatter plot;

Technically is was simpler to average them out as

score = ( Product[ score(a,b) | forall (a,b) in the scatter plot])^(1/n), where n is the number of points in the scatter plot.

So that’s how it is currently done.

Details:

The statistical meaning of the individual point score is the predictive lift for the model M measured at that point. It is essentially the same notion as the Predict Likelihood fraction for the case contributed by the continuous attribute for which the scatter plot has been built.

The specific formula for this is score(a,b) = pdf( N(a, predictStdev), b) / pdf( N(a, marginalStdev), marginalMean)

where N(mu, sigma) is the normal distribution with mean of mu and Stdev sigma and

pdf(N(mu, sigma), x) is its probability density function described by exp((x-mu)^2/(2*sigma))/sqrt(2Pi)/sigma.