Using Manjaro, I freshly installed PostgreSQL with an user-defined data-directory. PostgreSQL is running fine, but I can't find the postgresql*.log(s), which I used to find in /var/log/postgresql on my former system. In ksystemlog I've seen an error, that I forced by
select * from non_exist_table;
but I'm wondering, if there is no longer the postgresql*.log.
Thank you!
Here is my postgresql.conf.
With logging_collector=off, the logs will just spew to the stderr of the postmaster process. That could have been redirected to a file, or just going to some tty someplace, or just be thrown away. You would have to look at the code which launches the database server.
Related
I was trying to follow the instructions from postgresqltutorial to load a sample database into postgresql using pgadmin. But after the database was restored(since I can query data from the database), the process watcher just won't go away, and it keeps saying that the command is "running"(as of this writing, it has been running for over 400 thousands seconds, but the size of the sample database is just a few megabytes). Reboot and reinstallation couldn't fix the problem.
Here are some screen shots:
And when I click "click here for details":
I am using postgresql 9.6 with pgadmin4 on windows 10. So what's going on here? Is it a bug? How can I get rid of the process watcher?
I had the same issue with posgresql 9.5 and pgAdmin4 on Windows 7. I solved it without loosing server list by opening %APPDATA%\pgAdmin\pgadmin4.db file with SQLite Manager (Firefox Add-on) and deleting all entries from the 'process' table.
This is a bug in pgAdmin4 & reported,
https://redmine.postgresql.org/issues/1679
close pgAdmin, restart the system, open %APPDATA% and erase the folder pgAdmin and the pgAdmin is Ready to start without errors.
Greetings
At my work I was running a complex query. I cancelled it and went home yesterday. This morning in the back the query was impossible to be terminated, also with the 'terminate backend' functionality. A colleague of mine restarted the host machine where postgres is installed. After the machine restart, the postgres database sever would not start up.
In my log files I see the error:
'pg_ctl: this data directory appears to be running a pre-existing postmaster'
I am not sure how to handle this problem. I could try to fix it or try to extrapolate the data from the save files. What is the most logical step to take and do you know how to fix this?
Earlier it gave this error message :
2016-01-28 15:52:33 GMT FATAL: lock file "postmaster.pid" already exists
2016-01-28 15:52:33 GMT HINT: Is another postmaster (PID 2100) running in data directory "C:/PostgreSQL/9.1/data"?
UPDATE... I located the file postmaster.pid and deleted it. Now I am restarting the computer and hoping it will start.
UPDATE... It works now. I rebooted the computer and postgres just instantly started. Happy as a child but at the same time not fully satisfied because of the following forum: https://superuser.com/questions/553045/fatal-lock-file-postmaster-pid-already-exists . Here it is stated to NEVER delete the postmaster.pid because of possible data corruption. So because of that I will backup all databases I have in postgres now.
So if anyone can share some more light on my ICT adventure of today I would be very satisfied. That is why I will not state that this question is answered, since I have no idea what went wrong and perhaps will run into it again someday.
The explanation is pretty straightforward. PostgreSQL writes the process ID to a file called postmaster.pid — the presence of the file is supposed to indicate that the server is running. When the PostgreSQL shuts down cleanly, it removes the postmaster.pid file.
However, when your colleague restarted the host machine, the PostgreSQL server got killed without having had a chance to remove the postmaster.pid file. Therefore, when you tried to start PostgreSQL, the presence of the file made it look complain that the server was already running.
This answer provides more complete advice. In general, you should never delete postmaster.pid for no good reason, because it's supposed to help prevent two servers from running at once on the same data files. However, if you are certain that the process indicated by the postmaster.pid file is already dead, then by all means just delete the stale PID file manually.
In windows Delete all running postgres processes and start the service
I am using helios Eclipse for debugging my code in postgresql.
My aim is to know how postgresql uses join algorithms during the join query, so I started to debug nodenestloop.c which is in the Executor folder.
I gave break points in that file, But whenever I try to debug that file, the control goes to main.c and never comes back,How do I constraint the control only to that particular file(nodenestloop.c)
Below are the following fields which I gave in Debug configurations of Helios Eclipse.
C/C++ Application - src/backend/postgres and
project - pgsql
I followed the steps given in the following link for running the program.
https://wiki.postgresql.org/wiki/Working_with_Eclipse#
I even uncheked the field "Start on Start up=main" , but When I do that, The step in and Step over buttons are not activated and the following problem has popped up.
Could not save master table to file '/home/ravi/workspace/.metadata/.plugins/org.eclipse.core.resources/.safetable/org.eclipse.core.resources'.
/home/ravi/workspace/.metadata/.plugins/org.eclipse.core.resources/.safetable/org.eclipse.core.resources (Permission denied)
So I started eclipse using sudo, but this time the following error has come in the console of eclipse.
"root" execution of the PostgreSQL server is not permitted.
The server must be started under an unprivileged user ID to prevent
possible system security compromise. See the documentation for
more information on how to properly start the server.
Could any one help me with this.
Thank you
Problem 1: User ID mismatch
Reading between the lines, it sounds like you're trying to debug a PostgreSQL instance that's running as the postgres user, or a different user ID to your own anyway. Hence your attempt to use sudo.
That's painful, especially when using an IDE like Eclipse. With plain gdb you can just sudo the gdb command to the desired uid, e.g. sudo -u postgres -p 12345 to attach to pid 12345 running as user postgres. This will not work with Eclipse. In fact, running it with sudo has probably left your workspace with some messed up file permissions; run:
sudo chown -R ravi /home/ravi/workspace/
to fix file ownership.
If you want to debug processes under other user IDs with Eclipse, you'll need to figure out how to make Eclipse run gdb with sudo. Do not just run all of Eclipse with sudo.
Problem 2: Trying to run PostgreSQL under the control of Eclipse
This:
"root" execution of the PostgreSQL server is not permitted. The server must be started under an unprivileged user ID to prevent possible system security compromise. See the documentation for more information on how to properly start the server.
suggests that you're also attempting to let Eclipse start postgres directly. That's very useful if you're trying to debug the postmaster, but since you're talking about the query planner it's clear you want to debug a particular backend. Launching the postmaster under Eclipse is useless for that, you'll be attached to the wrong process.
I think you probably need to read the documentation on PostgreSQL's internals:
Tour of PostgreSQL Internals
PostgreSQL internals through pictures
Documentation chapter - internals
Doing it right
Here's what you need to do - rough outline, since I've only used Eclipse for Java development and do my C development with vim and gdb:
Compile a debug build of PostgreSQL (compiled with ./configure --enable-debug and preferably also CFLAGS="-ggdb -Og -fno-omit-frame-pointer"). Specify a --prefix within your homedir, like --prefix=$HOME/postgres-debug
Put your debug build's bin directory first on your PATH, e.g. export PATH=$HOME/postgres-debug/bin:$PATH
initdb -U postgres -D $HOME/postgres-debug-data a new instance of PostgreSQL from your debug build
Start the new instance with PGPORT=5599 pg_ctl -D $HOME/postgres-debug-data -l $HOME/postgres-debug-data.log -w start
Connect with PGPORT=5599 psql postgres
Do whatever setup you need to do
Get the backend process ID with SELECT pg_backend_pid() in a psql session. Leave that session open; it's the one you'll be debugging.
Attach Eclipse's debugger to that process ID, using the Eclipse project that contains the PostgreSQL extension source code you're debugging. Make sure Eclipse is configured so it can find the PostgreSQL source code you compiled with too (no idea how to do that, see the manual).
Set any desired breakpoints and resume execution
In the psql session, do whatever you need to do to make your extension run and hit the breakpoint
When execution pauses at the breakpoint in Eclipse, debug as desired.
Basic misunderstandings?
Also, in case you're really confused about how all this works: PostgreSQL is a client/server application. If you are attempting to debug a client program that uses libpq or odbc, and expecting a breakpoint to trigger in some PostgreSQL backend extension code, that is not going to happen. The client application communicates with PostgreSQL over a TCP/IP socket. It's a separate program. gdb cannot set breakpoints in the PostgreSQL server when it's connected to the client, because they are separate programs. If you want to debug the server, you have to attach gdb to the server. PostgreSQL uses one process per connection, so you have to attach gdb to the correct server process. Which is why I said to use SELECT pg_backend_pid() above, and attach to the process ID.
See the internals documentation linked above, and:
PostgreSQL site - coding
PostgreSQL wiki - developer resources
Developer FAQ
Attaching gdb to a backend on linux/bsd/unix
I also faced similar issue and resolved it after some struggle
I misunderstood the following point under Debugging with child processes in the wiki (https://wiki.postgresql.org/wiki/Working_with_Eclipse).
5."Start postmaster & one instant of postgresql client (for creating one new postgres)"
The above step should be performed from terminal by starting postgres server and one client.
Hope this helps
Once this is done then debugger in eclipse needs to be started for C/C++ Attach to Application
This is a problem using stats(), or just when calculating the database size. Using postgresql in windows 7, localhost.
The problem after doing this is:
"could not stat file "base/17436/119145": Permission denied"
I spent a lot of time trying to fix this problem, until i realise what is really the problem about.
So i'm going to answer myself.
This could be for 2 reasons:
-User of database (login role) without enough permissions.
In this case, check if the user, for example "postgres", have all the controls and privileges active.
-If localhost, check your antivirus, Twice.
Statistics made by postgresql might be considered as a virus movement by many antiviruses (ESET in my case), is a false positive, the only solution is to locate the directory of the database (like \PostgreSQL\9.3\data) and create am exception to that directory in your antivirus software.
As you can see, this second option is not related to the database code it self.
Hope this help you.
In my case (as #JB suggested) restarting the PostgreSQL service will work in some instances.
in my case I got this error after broke an "reindexdb.exe database" command with Ctrl-C. I was running it on Windows 7 command prompt.
Stop-Start of the PostgreSQL service solved the problem.
I get this exception in PostgreSQL:
org.postgresql.util.PSQLException: ERROR: could not access file "$libdir/plpgsql": No such file or directory
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:1721)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1489)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:193)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:452)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:337)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:236)
at org.apache.commons.dbcp.DelegatingStatement.executeQuery(DelegatingStatement.java:205)
I searched a lot and most solution points to a wrong installation. But this is my test db which has been running without issues for a long time. Also inserts are working. Issue occurs only on select queries.
Apparently, you moved your PostgreSQL lib directory out of place. To confirm this, try the following in psql:
> SET client_encoding TO iso88591;
ERROR: could not access file "$libdir/utf8_and_iso8859_1": No such file or directory
If you get an error message like this, then my theory is correct. You'll need to find out where those files ended up, or you can reinstall PostgreSQL to restore them.
To find out what $libdir is referring to, run the following command:
pg_config --pkglibdir
For me, this produces:
/usr/lib/postgresql
I have the same problem: the other postgres server instance (8.4) was interfering with the 9.1 one; when the 8.4 instance is removed it works.
the other instance can sometimes be removed from the system while still running (e.g. you do a gentoo update and a depclean without stopping and migrating your data). so the error seems particularly mysterious.
the solution is usually going to be doing a slot install/eselect of the old version (in gentoo terms, or simply downgrading on other distros), running its pg_dumpall, and then uninstalling/reinstalling the new version and importing the data.
this worked pretty painlessly for me