Wireless WiFi antenna not plugged, despite it being installed
How do I install drivers for Realtek RTL8812BU?
Editing question title creates whole new question and other question list problems Why does stdafx.h work the way it does? As usual, when my brain's messing with something I can't figure out myself, I come to you guys for help :)  This time I've been wondering why stdafx.h works the way it does? To my understanding it does 2 things:   Includes standard headers which we might (?) use and which are rarely changed Work as a compiler-bookmark for when code is no longer precompiled.   Now, these 2 things seems like two very different tasks to me, and I wonder why they didn't do two seperate steps to take care of them? To me it seems reasonable to have a #pragma-command do the bookmarking stuff and to optionally have a header-file a long the lines of windows.h to do the including of often-used headers... Which brings me to my next point: Why are we forced to include often-used headers through stdafx.h? Personally, I'm not aware of any often used headers I use that I'm not already doing my own includes for - but maybe these headers are necessary for .dll generation?  Thx in advance SQL Query; Admin Log System; Foreign Keys; Retriving multiple rows form different tables at once Table A (users)  id     | name   | ip 52433    Yashas   1.1.1.1 512      Admin    5.6.7.8   Table B (admin_record)  id    | admin | time    | date    | reason | action  52433   512     2312352   1213213   Test     WARN   id is FOREIGN key  Table B keeps a log of all actions an administrator takes on his users. And the table A stores the account information of the users &amp; administrators.  I am trying to display a list of actions taken by a administrators on a user.   I want to write a query which gets me all the rows of table B where id = fixed number.  Here is what I want to display:  "Administrator1 [Name]" took action on "User Name" for "[Note]" on XX/XX/XXXX. "Administrator2 [Name]" took action on "User Name" for "[Note]" on XX/XX/XXXX. "Administrator3 [Name]" took action on "User Name" for "[Note]" on XX/XX/XXXX.   All I have is the user's id using which I need to obtain all the entries in the log along with the administrator names. I need to obtain the admin's name, users name and all the contents of table B related to a particular user in one single query. If possible, I want the to change the field name(not literally change, but want the SQL server to send the data with new field names to separate admin name &amp; user name) of the admin's name to admin_name and user's name as . I mean something like this  SELECT users.name AS admin_name WHERE users.id = %i  AND SELECT users.name AS user_name WHERE users.id = %i   (the query isn't correct,it us just an example to show what I am trying)  Progress so far:   SELECT player.name, player.ip, admin.name, record.date, record.time, record.action, record.reason FROM admin_record AS record JOIN users AS player ON player.id = record.id JOIN users AS admin ON admin.id = record.admin WHERE player.id=%i   where admin_record is table B &amp; users is table A. I am using a linux server which has 128GB of memory and 24 cores. I use top to see how much it is used. Its output is pasted at the end of the post. Here are two questions:  (1) I see that each of the running processes occupies a very small percentage of memory (%MEM no more than 0.2%, and most just 0.0%), but how the total memory is almost used as in the fourth line of output ("Mem:  130766620k total, 130161072k used,   605548k free,   919300k buffers")? The sum of used percentage of memory over all processes seems unlikely to achieve almost 100%, doesn't it?  (2) how to understand the load average on the first line ("load average: 14.04, 14.02, 14.00")?   Thanks and regards!  Edit:  Thanks!  I also really like to hear some rough numbers based on used percentage of memory to determine if a server is heavily loaded, since I once became the one who cramed the server without understanding the current load.  Is swap regarded as almost the same as memory? For example, when memory and swap are almost of same size, if the memory is almost running out but the swap is still largely free, may I just view it as if the used percentage of memory + swap is still not high and run other new processes?  How would you consider together CPU or memory (or memory + swap) usage? Do you become worried if either of them reaches too high or both?  Output of top：  $ top    top - 12:45:33 up 19 days, 23:11, 18 users,  load average: 14.04, 14.02, 14.00 Tasks: 484 total,  12 running, 472 sleeping,   0 stopped,   0 zombie Cpu(s): 36.7%us, 19.7%sy,  0.0%ni, 43.6%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st Mem:  130766620k total, 130161072k used,   605548k free,   919300k buffers Swap: 63111312k total,   500556k used, 62610756k free, 124437752k cached    PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND  6529 sanchez   18  -2 1075m 219m  13m S  100  0.2  13760:23 MATLAB 13210 timothy   18  -2 48336  37m 1216 R  100  0.0   3:56.75 absurdity 13888 timothy   18  -2 48336  37m 1204 R  100  0.0   2:04.89 absurdity 14542 timothy   18  -2 48336  37m 1196 R  100  0.0   1:08.34 absurdity 14544 timothy   18  -2  2888 2076  400 R  100  0.0   1:06.14 gatherData  6183 sanchez   18  -2 1133m 195m  13m S  100  0.2  13676:04 MATLAB  6795 sanchez   18  -2 1079m 210m  13m S  100  0.2  13734:26 MATLAB 10178 timothy   18  -2 48336  37m 1204 R  100  0.0  11:33.93 absurdity  12438 timothy   18  -2 48336  37m 1216 R  100  0.0   5:38.17 absurdity 13661 timothy   18  -2 48336  37m 1216 R  100  0.0   2:44.13 absurdity 14098 timothy   18  -2 48336  37m 1204 R  100  0.0   1:58.31 absurdity 14335 timothy   18  -2 48336  37m 1196 R  100  0.0   1:08.93 absurdity 14765 timothy   18  -2 48336  37m 1196 R   99  0.0   0:32.57 absurdity 13445 timothy   18  -2 48336  37m 1216 R   99  0.0   3:01.37 absurdity 28990 root      20   0     0    0    0 S    2  0.0  65:50.21 pdflush 12141 tim       18  -2 19380 1660 1024 R    1  0.0   0:04.04 top  1240 root      15  -5     0    0    0 S    0  0.0  16:07.11 kjournald  9019 root      20   0  296m 4460 2616 S    0  0.0  82:19.51 kdm_greet     1 root      20   0  4028  728  592 S    0  0.0   0:03.11 init     2 root      15  -5     0    0    0 S    0  0.0   0:00.00 kthreadd     3 root      RT  -5     0    0    0 S    0  0.0   0:01.01 migration/0     4 root      15  -5     0    0    0 S    0  0.0   0:08.13 ksoftirqd/0     5 root      RT  -5     0    0    0 S    0  0.0   0:00.00 watchdog/0     6 root      RT  -5     0    0    0 S    0  0.0  17:27.31 migration/1     7 root      15  -5     0    0    0 S    0  0.0   0:01.21 ksoftirqd/1     8 root      RT  -5     0    0    0 S    0  0.0   0:00.00 watchdog/1     9 root      RT  -5     0    0    0 S    0  0.0  10:02.56 migration/2    10 root      15  -5     0    0    0 S    0  0.0   0:00.34 ksoftirqd/2    11 root      RT  -5     0    0    0 S    0  0.0   0:00.00 watchdog/2    12 root      RT  -5     0    0    0 S    0  0.0   4:29.53 migration/3    13 root      15  -5     0    0    0 S    0  0.0   0:00.34 ksoftirqd/3 Alternating sum of squares of binomial coefficients If you are falling, can you Misty Step to the ground to avoid damage? If I fall off a cliff - say, 1000 feet - can I wait (readied action?) until I am near enough to the ground (my understanding is you fall 500 ft/round) then  safely to the ground? Or, does the momentum from the fall carry over through the teleport and I still splatter across the rocks? How to have a one-to-many relationship with a privileged child? Force figure placement in text I have a problem when a lot of figures are in question. Some figures tend to "fly around", that is, be a paragraph below, although I placed them before that paragraph. I use code:  \begin{figure}[ht] \begin{center} \advance\leftskip-3cm \advance\rightskip-3cm \includegraphics[keepaspectratio=true,scale=0.6]{slike/visina8} \caption{} \label{visina8} \end{center}\end{figure}   to place my figures. How can I tell latex I REALLY want the figure in that specific place, no matter how much whitespace will be left? I'm trying to prove that the characteristic of any field $F$ is either $0$ or a prime number, but I have no idea what to do.  Help? Getting a FILE* from a std::fstream Is there a (cross-platform) way to get a C FILE* handle from a C++ std::fstream ?  The reason I ask is because my C++ library accepts fstreams and in one particular function I'd like to use a C library that accepts a FILE*. Where's the Strangedupe blog post? Previously, in order to explain the benefits of (certain limited kinds of) duplication on Stack Exchange sites, I've seen a blog.stackoverflow blogpost with the words "Dr. Strangedupe" in the title.  The post comes up in a search on the new blog, but       Can we please bring this post back? I'd love to link to it when , to reassure the questioner that there is value in not deleting their question because of search terms, but the blog post explained it a lot better than I could in a comment. I have read the thread regarding , but it does not answer my question.  I am confused about the notation for change in Physics. In Mathematics, $\delta$ and $\Delta$ essentially refer to the same thing, i.e., change. This means that $\Delta x = x_1 - x_2 = \delta x$. The difference between $\delta$ and $d$ is also clear and distinct in differential calculus. We know that $\frac{dy}{dx}$ is always an operator and not a fraction, whereas $\frac{\delta y}{\delta x}$ is an infinitesimal change.   In Physics, however, the distinction is not as clear. Can anyone offer a clearer picture? Why is this trigger finding a null value despite the field being populated? Continuous function on R which tends to infinity on open interval must have a minimum Suppose we have $f : \mathbb{R} \to \mathbb{R}$ continuous and $$\lim\limits_{x \to \pm \infty} f(x) = \infty.$$  Then must $f$ have a minimum on $\mathbb{R}$?  Intuitively it seems so, and it's easy to prove for some arbitrary closed interval in $\mathbb{R}$ with the Extreme Value Theorem, but how can we apply that to an open interval like $(-\infty, \infty)$? Is "89.9%" singular or plural? I’m writing a dissertation on network security. I’m unsure which of the following to use:   ...89.9%, which is 57 million users.  ...89.9%, which are 57 million users.   Technically it should be are because it refers to a plural amount of people, but it doesn’t sound right to me considering that 57 million is in a sense one group. Computing second partial derivative with polar coordinates Consider the polar coordinates with $x=r\cos\theta$ and $y=r\sin\theta$.  I can show using the chain rule that $$\frac{\partial}{\partial x} = \frac{x}{r} \frac{\partial}{\partial r} -\frac{y}{r^2} \frac{\partial}{\partial \theta}$$   What is the method to compute $\dfrac{\partial^2}{\partial x^2}$? I don't know how to do it. How can I rewire half switched receptacles? In my bedroom the bottom half of all receptacles are controlled by one switch. Is it possible to have just one receptacle with top and bottom hot all the time?  The top half is hot all the time the bottom half is controlled by one switch.  Keep in mind there are six other receptacles in this room that are the same way controlled by the same switch. When I took the receptacle out the right side tab had been removed.  The top right screw had a black wire, the bottom right had a red wire, the top and bottom left screws had separate white wires.  I changed the receptacle out as suggested, I capped off the red wire and I capped off the white wire that was attached to the bottom left screw. I attached the other white wire to the top left screw and attached the black wire to the top right screw. I now have none of the receptacles working at all. What did I do wrong? In the Android app, left sidebar, there is an editable list of "Your Sites". In the editing pane, the sites are re-orderable (although awkwardly), and the order one places the sites in there is preserved, even after quitting the app and returning to this pane. One expects that order to be reflected in the "Your Sites" portion of the left sidebar when the editing pane is closed, but it is not.  I'm not sure what is determining the order of the sites in the left sidebar, it doesn't seem to be by date they were "pinned" into the list one wants to show, either. I use object != null a lot to avoid . What is an alternative to: if (someobject != null) {     someobject.doCalc(); } I thought that there was no need to scan for viruses either in Ubuntu or any Linux distros until I found virus scanner packages clamtk and klamav in Ubuntu software center yesterday.  This leads to the following questions:   How do viruses differ between Linux and Windows? How do the strategies for protection differ between Linux and Windows? Should a virus scanner package be installed on my system? If so, which would be a better option?