While trying to export a query result set from PGAdmin4 on PostgreSQL12 to a CSV I am encountering the following error: ERROR:  could not open file &quot;/home/linuxusername/Downloads/data.csv&quot; for reading: Permission denied HINT:  COPY FROM instructs the PostgreSQL server process to read a file. You may want a client-side facility such as psql's \copy. SQL state: 42501  I'm somewhat new to PGAdmin but am familiar with Linux and SQL. Is there a configuration setting that I'm unaware of to allow PGAdmin to read and write to files and directories of Linux users? Using the /tmp works fine, but it's a pain to have to keep moving files to and from other directories and it's seriously cramping my work flow and slowing me down. Any help is much appreciated.
I have asked this question on SO but perhaps that was the wrong location. Apologies for double posting but the question may have a better audience here.  The original question is:   And the text is below. Thanks.    When running the postgresql [9.3] "COPY TO" functionality, the postgres user creates a file. I have told it to put the file in the tmp directory (although this can be changed if needed).  This is run as part of a cron job, the user is an "export" user set up especially for this task. The end goal is for the exported file to end up in /home/export/created_file.csv.  1) postgres can't stash the exported file straight into the home directory of another user without setting up the folder to be overly permissive.  2) the export user can copy the file from /tmp to it's home directory, but then can not clean up (delete) the postgres owned file in /tmp.  This is a daily process and so old files will need to be deleted in some way. I can add a cron job to clean up the files afterwards but I was hoping for a cleaner solution - either a way to change the permissions on the file that postgres creates, or some way to give the export user the additional permission of being able to delete that file in advance of it's creation.  Giving the export user the same permissions as postgres in general however isn't an option, as it would then have free reign over the database.  Any advice, be it unix based or postgres based would be very welcome, thanks.
Converting a list of tuples into a dict I have a list of tuples like this:  [ ('a', 1), ('a', 2), ('a', 3), ('b', 1), ('b', 2), ('c', 1), ]   I want to iterate through this keying by the first item, so, for example, I could print something like this:  a 1 2 3 b 1 2 c 1   How would I go about doing this without keeping an item to track whether the first item is the same as I loop around the tuples? This feels rather messy (plus I have to sort the list to start with)... JavaScript open in a new window, not tab I have a select box that calls window.open(url) when an item is selected.  Firefox will open the page in a new tab by default.  However, I would like the page to open in a new window, not a new tab.    How can I accomplish this? I have just asked a question on   I read from this meta answer  that suggested     From a desktop support perspective there are certainly cases where a   large(r) number of machines will be affected by something, in which   case it's appropriate for SF. There are then others that are isolated   to a single computer, these tend to be the ones I vote to move to SU.   Since my question is clearly not about a single computer and is external to a single computer, I turned to ServerFault. I thought the question is about how to replicate a network admin strategy on my own (home) network. My question is, however, marked as off-topic, and I did see that homenetwork questions are off-topic. But this is not a single computer issue either.  My question is:  Where should such home/small network questions be asked?  What's the real difference between "professional" networks and the smaller networks that I build for my home or lab with a handful computers?  -- UPDATE --  The question asked here is different from the said duplicate question  as that question is about the difference among computer science and programming SE sites. It has nothing to do with network administration, whether it's large or small networks. None of the two SE sites in question (Server Fault and Super User) is even mentioned in the question or in the 2 cited answers.  -- UPDATE2 --  This question is not a duplicate of , which was cited in the OP and was the cause of this question. That question does not cover the overlapping area of small networks, which could both be for work and for home network. Energy conservation and interference I have a problem with energy conservation in case of interfering waves.  Imagine two harmonic waves with amplitudes $A$. They both carry energy that is proportional to $A^2$, so the total energy is proportional to $2A^2$. When they interfere, the amplitude raises to $2A$, so energy is now proportional to $4A^2$ and bigger than before.  The equivalent question is what happens to the energy with the superposition of two waves that interfere destructively.  Also, if someone could comment on the statement about this problem in my physics book (Bykow, Butikow, Kondratiew):      The sources of the waves work with increased power during the interference because they feel the wave from the other source. Multiple (diamond) inheritance compiles without "virtual", but doesn't with "To be subject to" vs. "to be subjected to" I read an article from  today which stated:     TTC workers are subject to alcohol and drug testing.   A later paragraph of the same article repeated it, except it used subjected to instead of subject to.  I have rarely seen the use of subjected to before. Is it legitimate in English as well? Why didn’t the author just keep it consistent by using subject to throughout the article? Does using varieties of forms enrich the expressions within an article? Phase shift of 180 degrees of transversal wave on reflection from denser medium Can anyone please provide an intuitive explanation of why phase shift of 180 degrees occurs in the Electric Field of a EM wave, when reflected from an optically denser medium?  I tried searching for it but everywhere the result is just used.The reason behind it is never specified. Can somebody help me calculate the following integral:  $$\int\limits_{1/3}^{3}\frac{\arctan(x)}{x^2-x+1}\;\mathrm{d}x$$  I have tried integration by parts, but I got stuck in it. Wolfram also didn't help me.  I would be happy to get some hints. HDMI to VGA convert I just bought a new HP Pavilion dv7t Quad Edition laptop that has HDMI out. I already have a couple of monitors that are VGA and I'd like to hook up one of these to dual monitors.  I've read some sketchy reviews of products that try to convert directly from HDMI (digital) to  VGA (analog), so I was wondering if someone has a good recommendation on how to hook these two together. When to use a hyphen to coin a new word and when to omit a hyphen? Someone has asked for answer to these topics. However, I still want someone to provide me with simple and universal answers. I recently read a sentence from the English-speaking person. It is in an article. It is, ' The available options for mitigating pad cratering are not universally effective (see link below), but they may be helpful on a case by case basis until more crack resistant laminates are developed and become available.  '  If I am to write this, I will use 'a case-by-case basis until more crack-resistant laminates'   Can anyone tell me when to use a hyphen to coin a new word? What is the origin of elements heavier than iron? In all the discussions about how the heavy elements in the universe are forged in the guts of stars and especially during a star's death, I usually hear that once the star begins fusing lighter atoms to produce iron (Fe) that's the end of the star's life and the whole system collapses onto itself; and based on how massive the star was initially, it has different outcome - like a white dwarf, a neutron star or a black hole. I have rarely heard a detailed explanation of how the elements heavier than iron are produced. I would appreciate a convincing explanation of this process. Preview: PDF Highlighting & Search Stop Working until Restart A problem has recently become much more prevalent for me when using Preview to search PDFs for text (using Command + F or the search box in the upper right).  At first, everything generally seems to go fine:    (as it should be) a list of thumbnails appears in the sidebar, indicating all of the pages that contain the search term. Generally, though not always, the term I search for will be highlighted on the first page that it occurs on.   But, after this, things quickly start malfunctioning:   Generally speaking, if I click on thumbnails lower on the list, Preview will take me to that page in the PDF (like it used to).  But, it will no longer highlight the searched for terms. Instead, Preview will make a low-pitched beeping noise of the sort that occurs when one tries to perform some un-permitted action in a variety of mac situations. Furthermore, once this occurs, I cease being able to make any highlights at all in the document I am viewing with Preview.  In fact, I can't even select any text any more.   Below is a list of unsuccessful efforts to resolve this:   Closing the side bar does not work to resolve this. x-ing out the search box in the upper right does not resolve this. Selecting the "Tools" menu and then "Text Selection" does not work either, nor does clicking on the text selection icon in the edit panel. If I quit preview and then re-open the PDF, I am able to highlight again.  But, the problem will re-surface as soon as I try performing another search. Working with the same files in other PDF programs (e.g. Skim, Acrobat, etc.) poses no problems.  I'm quite certain it isn't a problem with the underlying PDFs. None of the responses to  resolve this.  (indeed, I supplied one such response myself a while ago, but that trick and the others no longer work).   I've used Preview for many years without problem.  This issue started cropping up relatively recently for me, I believe within the past 3-4 months.  I had hoped that upgrading to Catalina might resolve it, but it did not.    I'd like to think I am fairly sophisticated with computers (I have a reputation of close to 8,000 on the main stackoverflow page), but I am baffled by this.  I also don't have a good handle on how I can get diagnostic information or how I can create a reproducible example.    Any leads on how to tackle this would be greatly appreciated. How to add texture to fill colors in ggplot2 Let $\alpha,\beta,\gamma$ be the roots of $x^3-3x^2+1 = 0$. Prove that $$\alpha^n+\beta^n+\gamma^n \equiv 4^n+5^n+(-6)^n \pmod{17}$$ where $n$ is an integer.   It sort of makes sense why they are congruent since we can say $x^3-3x^2+1 \equiv (x-4)(x-5)(x+6) \pmod{17}$, but since $\alpha,\beta,\gamma$ aren't integers, how do we prove this? I used sculpting on a plane, and things looks great. However, when I press P to play, the whole ground become a mess. I can see through it in various places, and there are also nasty looking black edges everywhere.  another problem, I made a UV Sphere to display the sky, but when I press , P to play it disappears! There is a socket related function call in my code, that function is from another module thus out of my control, the problem is that it blocks for hours occasionally, which is totally unacceptable, How can I limit the function execution time from my code? I guess the solution must utilize another thread. How to add user to a group from Mac OS X command line? trying to add a user to a group from the command line but can't figure out how?   Specifically this is on Mac OS X Server 10.5.8  like to add user to 'admin' and 'wheel' groups What does the tilde (~) mean at the end of a filename? What is the file with the ~ at the end of the filename for?  $ ls # aliased to add flags -rwxrwxr-x  1 durrantm  2741 May 16 09:28 strip_out_rspec_prep_cmds.sh~* drwxrwxr-x 13 durrantm  4096 May 16 14:21 ../ -rwxrwxr-x  1 durrantm  2221 May 16 14:58 strip_out_rspec_prep_cmds.sh*   This is not the same as .swp files which are there while editing.  The two files have quite a few differences and the newer file (no ~ at the end) has the most recent changes and those changes are not in the older (~) file.  Looks like I can delete it? My interest in Blender comes from wanting to use it to model physical structures and produce architectural drawings; what I have so far is really impressive, but there doesn't seem to be too much information about my particular interest.   Are there any (Blender-) resources that would be particularly useful for architects? E.g. packages of standard 'elements' like windows, doors, roofs or whatever, or perhaps a discussion group specifically for architects? I love the  that was recently added onto Stack Exchange. However, this feature seems to be missing in per-site metas.  For instance:  Server Fault Meta:    DBA Meta    The parent websites, do have the edit/improve this post link however.