I am running the following queries in MS SQL Server (version 2016 if that matters).  SELECT DISTINCT Job_Number FROM table_A WHERE Job_Number IS NOT NULL   returns 2376 rows  SELECT * FROM table_A WHERE Job_Number IN (SELECT DISTINCT [House Bill] FROM table_B)   returns 137 rows  However,  SELECT * FROM table_A WHERE Job_Number NOT IN (SELECT DISTINCT [House Bill] FROM table_B)`   returns 0 rows. I would expect this would return 2239 rows (i.e. 2376 - 137).   Is there any fundamental concept of NOT IN that I have yet to understand here?
This issue came up when I got different records counts for what I thought were identical queries one using a not in where constraint and the other a left join. The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the concept.  To state it simply, why does query A return a result but B doesn't?  A: select 'true' where 3 in (1, 2, 3, null) B: select 'true' where 3 not in (1, 2, null)   This was on SQL Server 2005. I also found that calling set ansi_nulls off causes B to return a result.
I am thinking of buying a digital SLR camera. What things should I be looking for? Migrate site from dev environment to production server - 404 errors We completed development on our dev environment and I copied the files over from the dev server to the production server through FTP.   Then through back up and migrade module, I made a back up of the SQL database. I created a new database through Plesk with the same name, username and password. I then imported the SQL database into the new server through phpmyadmin. I go to the URL and get the Site Maintenance message (which is correct, I placed the site in maintenance mode before copying the files over) but cannot navigate to any sub pages. Generally I can add /user or /admin to the end of the url and get the login screen. However all I get are 404 errors. I was talking to a friend who owns a Mac. He has his set up so that when he swipes three fingers across his touchpad, it moves to the workspace in that direction. Is it possible to set this up in Ubuntu? How can I shorten my command line (bash) prompt? Currently it is:   michael@Castle2012-Ubuntu-laptop01:~/Dropnot/webs/rails_v3/linker/spec/controllers$   Outside of renaming my machine and directory structure...  How could I make it be something more like:  michael:controllers$ Could normal users have an easier way to flag for migration? The indexer into Dictionary throws an exception if the key is missing.  Is there an implementation of IDictionary that instead will return default(T)? I know about the TryGetValue() method, but that's impossible to use with LINQ. Would this efficiently do what I need?: myDict.FirstOrDefault(a =&gt; a.Key == someKeyKalue);  I don't think it will as I think it will iterate the keys instead of using a Hash lookup. Does a photon exert a gravitational pull? sir, problem about a host file sir, over department created a host file to run over office program in windows, but they give us dell system having operating system ubuntu 16.4 now my question is that how this add file in ubuntu to run the program. the windows command is given below  TO ACCESS FIORI - Please Follow the Instructions in this Video  Path:- C:\Windows\System32\drivers\etc  Copy attached Hosts File in the above path.  Fiori Link to access SAP in Google Chrome: How to include PDF pages without a newpage before the first page? Why do we need a diagonal matrix? Apart from simplifying matrix powers, why do want to diagonalize a matrix? Do they have any appealing application which can be used to motivate to study diagonal matrices.  Thanks for any answers. Help, Creating a test class for an invocable method (code coverage @ 0%) Getting javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher? Resource for Blender addons? Admin privileges requiring for installing a package build though Packages Using osx 10.9 and packages for making package installer.  While installing a package made using Packages in /Applications location on a osx 10.9 machine, installer is asking for Admin password. Even though I had unchecked 'Require admin password for installation' while package making.  So, how to avoid this i.e a non-admin user should install this package. Package should install in /Applications location, so that non-admin user can use the app.  I check  and ibus Avro in Ubuntu 14.04 LTS I used the instructions given  to install ibus Avro in my ubuntu 14.04 LTS (64 bit) but ibus avro was not installed. Can anyone help me to solve this case? After giving the commands in terminal nothing happens. Distributing elements across a list of lists I found this animal, which I suspect it's an insect, on the floor of a kitchen in Spain some days ago. It's about 8-10 mm long. I don't think I've ever seen it before. What is it? The migration is from the local environment to the production environment. The production environment has run some time and created a lot of articles.   In order to add new things to my site, I added a custom theme and installed CCK, Views and other modules in my local test environment. Now that the local test environment is finished, how do I migrate it to the production environment, without destroying the content of its database? For a multiclass imbalanced problem, accuracy is not a good metric to evaluate model performance. Equally, accuracy is a global metric, so nothing like accuracy per-class (doesn't make sense). Scikit-learn provides the classification_report  function so one can evaluate model's precision/recall per class, e.g: classification_report(y_true, y_pred, target_names=target_names)               precision    recall  f1-score   support       Class:0      0.703     0.896     0.788      4491      Class:1      0.048     0.147     0.072        75      Class:2      0.368     0.503     0.425      1097      Class:3      0.937     0.850     0.892     17162      Class:4      0.529     0.177     0.265       311      accuracy                          0.832     23136    macro avg      0.517     0.515     0.488     23136 weighted avg      0.856     0.832     0.838     23136  Are there other metrics that evaluate per-class so I can evaluate my model across more metrics than precision/recall/f1? The goal is to assess the model on a per-class basis. Doubts on the axiom of union? I'm reading Guerino Mazzolla's Comprehensive Mathematics for Computer Scientists 1:     Axiom 3 (Axiom of Union) If $a$ is a set, then there is a set      $$\{x| \text{ there exists an element } b \in a \text{ such that } x\in b \}$$      This set is denoted by $\cup a$ and is called the union of $a$.    This axiom seems to take elements from inside of a set of sets, for example in the set: $a=\{\{u_1,u_2 \},\{u_3,u_4 \} \}$, there are two elements $b\in a$, then the mentioned set created by the axiom is $\{u_1,u_2,u_3,u_4 \}$.           The axiom seems to imply that the set $a$ must have a set inside of it for it to work, what if it  have an element that is not a set? (I'm not sure if this is possible, but I remember of having read something about the difference of sets and elements).         There's also an extension of my proposal, In the same book (and also in others) I've seen that the natural numbers are defined as:   $$\begin{eqnarray*}   {0}&amp;=&amp;{\emptyset} \\    {1}&amp;=&amp;{\{\emptyset\}} \\    {2}&amp;=&amp;{\{ \{\emptyset\}\}} \\    {3}&amp;=&amp;{\{ \{ \{\emptyset\}\}\}} \\   {\vdots}&amp;=&amp;{\vdots} \end{eqnarray*}$$  Then the singleton $\{ 3\}$ could be seen as $\{ \{ \{ \{\emptyset\}\}\}\}$, which could mean that   $$\cup \{ 3 \}=\cup\{ \{ \{ \{\emptyset\}\}\}\}= \{ \{ \{\emptyset\}\}\}=\{2 \}$$          Then the union could also be seen as the antecessor of a number?            Using the framework I provided, I see some ambiguity, look:   $$\{ \{ \{\emptyset\}\}\}=\{2 \}$$          I decided to interpretate it this way, but from the notation it's not clear in which pair of brackets I should stop, I guess that $\{ \{ \{\emptyset\}\}\}=\{2 \}$ but it could also be the case that $\{ \{ \{\emptyset\}\}\}=3$. I could want a singleton with a $2$ inside of it and a $3$ outside a set, no?