## performance – OLA job failed due to below error and having sufficient disk space,autogrowth enabled on server

Database context: (OperationsManager) (SQLSTATE 01000)
Command: ALTER INDEX (idxc_PerformanceData_26_TimeSampled) ON (dbo).(PerformanceData_26) REBUILD WITH (SORT_IN_TEMPDB = OFF, ONLINE = OFF) (SQLSTATE 01000)
Comment: ObjectType: Table, IndexType: Index, IndexType: Clustered, Incremental: N, RowCount: 0, ModificationCounter: 0 (SQLSTATE 01000)
Msg 50000, Sev 16, State 1, Line 214 : Msg 1101, Could not allocate a new page for database
‘OperationsManager’ because of insufficient disk space in filegroup ‘PRIMARY’.
Create the necessary space by dropping objects in the filegroup, adding additional files to the filegroup,
or setting autogrowth on for existing files in the filegroup. (SQLSTATE 42000)
Outcome: Failed (SQLSTATE 01000)

## For food photography, is my 550D 18-55 mm gun sufficient?

Depends on where you are shooting (indoors / dark relative to sunlight) and whether your 18-55mm lens is image stabilized

Food does not move. You only need one (or at most a few) shots. You can usually fill the frame with the subject, so 18 Mpix is ​​enough. So, food photography is the easiest photography to take when you consider the functionality of the camera.

One of the advantages of many 18-55mm lenses and cropping cameras is that they allow you to reach fully acceptable macro distances. Not good enough for insects, but certainly good enough for food.

However, if you photograph your food indoors, you will find that the interior lighting is very dim. It is darker inside than you think. So your photos may end up being shaken if taken without image stabilization at small apertures of the 18-55mm zoom.

So, if you find your photos are shaken and your 18-55mm is not a stabilized lens, replace the old 18-55mm lens with an 18-55mm stabilized lens. ;picture. I suggest going for (1, 2) STM versions of the lens; It is a much better value as it can shoot videos without autofocus ruining the audio track. It also doesn't look like a child's toy when in focus, which is an advantage. The older STM lens has better maximum magnification, so for food photos, I would prefer the old f / 3.5-5.6 STM to the new f / 4-5.6 STM.

If you want to get shallow depth of field effects for your food photos, add the 50mm f / 1.8 STM lens to your kit. Its improved close focus distance compared to the old 50mm f / 1.8 II lens allows for easier shots.

Your camera is not too old. Its resolution is quite good. Its low light performance may be slightly dated, but not too much. Buying a better camera can be a step backwards, such as a full-frame camera is worse for taking pictures of close-up subjects because of its large sensor, and the camera full-frame photo usually does not accept cropped lenses (or if so, with reduced resolution), so you also need new lenses – the best zoom lenses tend to have distance slightly worse minimum focus than inexpensive EF-S 18-55mm lenses.

So my suggestion is the "EF-S 18-55mm f / 3.5-5.6 IS STM" lens (but only if your current 18-55mm does not have a stabilizer), and the "EF 50mm f / 1.8 STM" lens. You should expect to pay between \$ 300 and \$ 400 for the two together. In particular, stabilized zoom lenses from 18 to 55mm can often be found very inexpensively as second-hand items (less than \$ 100 where I live), so even \$ 200 to \$ 300 might buy you a good food photography kit. If you buy a used 18-55mm, make sure that it is a stabilized image version. If you buy a used 50mm, make sure it is the STM version with an improved minimum focusing distance.

The easiest way to improve the colors and contrast of all the photos you take is to use a lens hood. Fortunately, EF-S 18-55mm lenses accept an EW-63C petal cap. The 50mm lens accepts a slightly worse ES-68 circular cover. Make sure to buy both if you find that your colors and contrast are lacking.

Once you have the most suitable lenses and caps for them, if you want to enhance your photos even more than what the lenses can help, take RAW photos and download Canon Digital Photo Professional. Use the Digital Lens Optimizer function and learn how to correct the exposure and make other settings.

## stochastic processes – Sufficient condition for the weak existence of a solution of an SDE

Please note that I am posting this question from MSE as it is very likely that it is not resolved and I could not get an answer from my colleges / teachers.

This is a well known result due to Skorokhod that if for the SDE:
$$dX_t = b (t, X_t) dt + sigma (t, X_t) dW_t$$
the coefficients $$b (t, x)$$ and $$sigma (t, x)$$ are supposed to be continued and demarcated then a weak existence holds.

On the book of Ikeda & Watanabe (in particular Theorem IV.2.3.), The authors state:

Given the continuous coefficients $$sigma (x)$$ and $$b (x)$$ time
Homogeneous markovian type SDE)

$$dX_t = b (X_t) dt + sigma (X_t) dW_t$$ Then for any probability measure
$$mu$$ with a compact support, there is a solution for the SDE whose
the initial distribution coincides with $$mu$$.

(It should be noted that the resulting solution can be explosive, but nevertheless it could be "solved" by assuming the square integrability of the initial condition and the linear growth.)

I am looking for other references regarding this particular result (which does not seem so well known). Neither Karatzas & Shreve nor Revuz & Yor seem to mention it. In Cherny and Engelbert's investigation, they simply mention the classic result due to Skorokhod and the same goes for Strook and Varadhan.

This is why I am curious about this result mentioned by Ikeda & Watanabe, which is less restrictive (even if it seems to apply only to the Markovian case which is homogeneous in time).

## How to find a complete and sufficient statistic of p

X1, X2, …, Xn are random variables independent of the normal distribution N (p, p ^ 2) where p is different from zero. I have no idea how to find a complete and sufficient statistic of p. Could someone help me?

## denial of service – mitigation of DDOS attacks – sufficient to analyze only GET / POST requests?

I am developing a DOS attack recognition module for application layer requests.
The application has a backend composed of several APIs. They are all connected via an API gateway (developed in Nodejs). Each request is recorded in a database and another server (written in python-Flask) analyzes the number of GET / POST requests for every 20 seconds and calculates the entropy of incoming requests and blocks any suspicious IP address by depending on the entropy value.

My question is, In order to defend myself against DOS attacks, should I consider other types of TCP packets other than HTTP (ex: ICMP).

My backend APIs do not allow any user to continue without logging in. In this case, is it worth developing the DOS attack recognition module.

## self-study – Is my teaching style sufficient to learn mathematics alone?

Just to simplify my request.

I started learning math at the age of 22 using textbooks without a teacher, essentially using a book pedagogy.

So I started with elementary math for college as preparation for my next 2 years of learning in maintenance of automated systems.

After having acquired some elementary notions of mathematics, I started my learning with real teachers. So I discovered new pedagogies from these teachers.

So my question is:

Can I continue to learn advanced mathematics on my own using these acquired pedagogies? I mean the teacher and the book.

## reference request – Necessary and sufficient conditions for an almost sure absolute continuity of regular conditional probabilities

Let $$( Omega, mathcal F, mathbb P)$$ to be a probability space. Yes $$mathcal G$$ is a sub$$sigma$$-domain of $$mathcal F$$, then the regular conditional probability $$mathbb P ^ { mathcal G}$$ for $$mathbb P$$ given $$mathcal G$$ is a $$mathcal G$$ measurable mapping of $$Omega$$ in the probability space on $$( Omega, mathcal F)$$ who satisfies
$$int_G mathbb P ^ { mathcal G} (A) d mathbb P = mathbb P (A cap G)$$
for everyone $$G in mathcal G$$ and $$A in mathcal F$$.

Assumption. For all sub-$$sigma$$-the fields $$mathcal G$$ of $$mathcal F$$, $$mathbb P ^ { mathcal G}$$ exist.

Question. Are there known necessary and sufficient conditions for the following statement? For all sub-$$sigma$$-the fields $$mathcal G$$ of $$mathcal F$$, $$mathbb P ^ { mathcal G}$$ is almost certainly absolutely continuous with regard to $$mathbb P$$, that is to say.
$$mathbb P big { omega in Omega: mathbb P_ omega ^ { mathcal G} ll mathbb P big } = 1.$$

Yes $$mathcal F$$ is generated numerically, then almost sure absolute continuity for each subalgebra follows. But I don't know if the reverse is true.

## Web development – is 1 server sufficient for authorization with SPA and the refresh token?

I am an experienced front-end developer. I learned the back-end of the asp.net web API to build a full-stack SPA that I have in mind. The battery is Asp.net WebApi + Angular + SQL database.

Problem: proper implementation of authentication

Important details

The application will only be used in my small country and will eventually be deployed on azure. It will have around 10-13 endpoints and I don't want to build a very complex and scalable solution just yet. The app will use token-based authentication. And here is my problem.

I learned most of Asp. I've read a lot about JWT, OAuth and possible attacks. So, according to many tutorials, I have built something.

Current implementation:

For now, I have only implemented one server that takes care of everything – exchange refresh tokens, get access tokens and read and write the resource . The access token expires one day and the refresh token does not expire at this time.

Current authentication flow:

1. Users correctly access the POST / api / users / register endpoint and receive a response with AccessToken and RefreshToken. The RefreshToken is registered in the database.

2. Users correctly access the POST / api / users / login endpoint and receive a response with AccessToken and RefreshToken. The old RefreshToken is replaced by the new one created.

3. Users correctly access the POST / api / users / refresh-token endpoint and receive a response with AccessToken and RefreshToken. The old RefreshToken is replaced by the new one created.

4. The user will log out but I have not implemented it yet. It will eventually delete the RefreshToken from the database.

The question:
Is the flow correct and is 1 server sufficient for authentication and resources in my case for production purposes?

## security by design – Is testing all executables without considering system files sufficient to determine if the system is infected with malware?

I learned that malicious activities will only be carried out by software (program) while malicious files (data to software installed in the system) cannot directly carry out malicious activities but they can be responsible for carrying them out. bring. system malware (for example, steganography). Therefore, these software must also be installed (automatically or manually) before performing their activity.

If this is true, is the search for malware in software before installation (triggered manually or automatically) sufficient to say that the system is 100% secure (given that our detector is ideally 100% accurate)?

## Is an hour connection sufficient for MAD, from Norwegian to Delta?

Is a connection of one hour sufficient to transfer from Norwegian to Delta to MAD, to finally arrive at LAX? We will travel without checked baggage.