I'm building a simple web app that will deploy on Heroku, and using a Postgres database that is filled with an object from Salesforce. I did that with HerokuConnect and that works.
Now I want to see the contents of the database so that I know the table names, and I already know you can't do that on Heroku itself. So, I tried to connect to the database locally via heroku pg:psql but everytime I do that I get the error:
---> Connecting to DATABASE_URL
DL is deprecated, please use Fiddle
psql: could not connect to server: Connection refused (0x0000274D/10061)
Is the server running on host "***.***.***.**" (**.***.***.***) and accepting
TCP/IP connections on port ****?
So that doesn't work. I tried the following but to no avail:
explicitly specifiying the name of the database
specifying host, user, database name, password, port and setting sslmode=require per the user guide and this question about connecting to a heroku postgresql database.
using the method above, but instead of using heroku psql I just used psql. That asked for a password but for a user I never created (a user with my corporate system name, because this is a corporate laptop)
reinstalling Postgres
Running heroku pg:info correctly lists my database information.
I am missing something, but I don't know what it is.
"DL is deprecated, please use Fiddle" is not an error but it's only a warning.
This is due to an issue with Ruby 2 on Windows.
I'm trying to setup the pgexercises data in my local machine. When I run: psql -U <username> -f clubdata.sql -d postgres -x I get the error: psql:clubdata.sql:6: ERROR: cannot execute CREATE SCHEMA in a read-only transaction.
Why did it create a read-only database on my local machine? Can I change this?
Normally the most plausible reasons for this kind of error are :
trying create statements on a read-only replica (the entire instance is read-only).
<username> has default_transaction_read_only set to ON
the database has default_transaction_read_only set to ON
The script mentioned has in its first lines:
CREATE DATABASE exercises;
\c exercises
CREATE SCHEMA cd;
and you report that the error happens with CREATE SCHEMA at line 6, not before.
That means that the CREATE DATABASE does work, when run by <username>.
And it wouldn't work if any of the reasons above was directly applicable.
One possibility that would technically explain this would be that default_transaction_read_only would be ON in the postgresql.conf file, and set to OFF for the database postgres, the one that the invocation of psql connects to, through an ALTER DATABASE statement that supersedes the configuration file.
That would be why CREATE DATABASE works, but then as soon as it connects to a different database with \c, the default_transaction_read_only setting of the session would flip to ON.
But of course that would be a pretty weird and unusual configuration.
Reached out to pgexercises.com and they were able to help me.
I ran these commands(separately):
psql -U <username> -d postgres
begin;
set transaction read write;
alter database exercises set default_transaction_read_only = off;
commit;
\q
Then I dropped the database from the terminal dropdb exercises and ran script again psql -U <username> -f clubdata.sql -d postgres -x -q
I was having getting cannot execute CREATE TABLE in a read-only transaction, cannot execute DELETE TABLE in a read-only transaction and others.
They all followed a cannot execute INSERT in a read-only transaction. It was like the connection had switched itself over to read-only in the middle of my batch processing.
Turns out, I was running out of storage!
Write access was disabled when the database could no longer write anything. I am using Postgres on Azure. I don't know if the same effect would happen if I was on a dedicated server.
I had same issue for Postgre Update statement
SQL Error: 0, SQLState: 25006 ERROR: cannot execute UPDATE in a read-only transaction
Verified Database access by running below query and it will return either true or false
SELECT pg_is_in_recovery()
true -> Database has only Read Access
false -> Database has full Access
if returns true then check with DBA team for the full access and also try for ping in command prompt and ensure the connectivity.
ping <database hostname or dns>
Also verify if you have primary and standby node for the database
In my case I had a master and replication nodes, and the master node became replication node, which I believe switched it into hot_standby mode. So I was trying to write data into a node that was meant only for reading, therefore the "read-only" problem.
You can query the node in question with SELECT pg_is_in_recovery(), and if it returns True then it is "read-only", and I suppose you should switch to using whatever master node you have now.
I got this information from: https://serverfault.com/questions/630753/how-to-change-postgresql-database-from-read-only-to-writable.
So full credit and my thanks goes to Craig Ringer!
Dbeaver: In my case
This was on.
This doesn't quite answer the original question, but I received the same error and found this page, which ultimately led to a fix.
My issue was trying to run a function with temp tables being created and dropped. The function was created with SECURITY DEFINER privileges, and the user had access locally.
In a different environment, I received the cannot execute DROP TABLE in a read-only transaction error message. This environment was AWS Aurora, and by default, non-admin developers were given read-only privileges. Their server connections were thus set up to use the read-only node of Aurora (-ro- is in the connection url), which must put the connection in the read-only state. Running the same function with the same user against the write node worked.
Seems like a good use case for table variables like SQL Server has! Or, at least, AWS should modify their flow to allow temp tables to be created and dropped on read nodes.
This occurred when I was restoring a production database locally, the database is still doing online recovery from the WAL records.
A little bit unexpected as I assumed pgbackgrest was creating instantly recoverable restores, perhaps not.
91902 postgres 20 0 1445256 14804 13180 D 4.3 0.3 0:28.06 postgres: startup recovering 000000010000001E000000A5
If like me you are trying to create DB on heroku and are stuck as this message shows up on the dataclip tab
I did this,
Choose Resources from(Overview Resources Deploy Metrics Activity Access Settings)
Choose Settings out of (Overview, Durability, Settings, Dataclip)
Then in Administration->Database Credentials choose View Credentials...
then open terminal and fill that info here and enter
psql --host=***************.amazonaws.com --port=5432 --username=*********pubxl --password --dbname=*******lol
then it'll ask for password, copy-paste from there and you can run Postgres cmds.
I suddenly started facing this error on postgres installed on my windows machine, when I was running alter query from dbeaver, all I did was deleted the connection of postgres from dbeaver and created a new connection
If you are using Azure Database for PostgreSQL your server gets into read-only mode when the storage used is near total capacity.
The error you get is exactly:
ERROR: cannot execute XXXXXXXXX in a read-only transaction
https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/concepts-compute-storage
I just had this error. My cause was not granting permission to the SEQUENCE
GRANT ALL ON SEQUENCE word_mash_word_cube_template_description_reference_seq TO ronshome_user;
If you are facing this issue with an RDS instance cluster, please check your endpoint and use the Writer instance endpoint. Then it should work now.
Issue can be dur to Intellij config:
Go to Database view> click on Data Source Properties (Shift + enter)> (Select your data source)>
Options tab> Under Connection : uncheck Read-only
For me it was Azure PostgreSQL failing over to standby during maintaince in Azure and never failing back to master when PostgreSQL was in HA mode. You can check this event in Service Health and also check which zone you current VM is running from. If it's 2 and not 1 them most likely that's the result of events described above.
I have PostgreSQL 9.3 version. I have created database name db1 now I need it to share with other users who all are connected with the LAN's to connect other applications with the same database.
In SQL Server: We can do this by selecting server name with login details.
Question:
Is it possible in PostgreSQL?
If yes, how can do this?
What is the procedure?
You will need to modify pg_hba.conf to allow remote connections to the database. Information about pg_hba.conf can be found here.
After that, you can connect programatically with a connection string, or similar to your image, with a GUI application like pgAdmin.
To connect (remotely or locally) from pgAdmin choose File -> Add Server... and enter the connection information into the dialog box. Here's an example of the window:
Your client computers will also need to have PostgreSQL drivers as well. If you're doing this in Windows, you'll probably be using ODBC. The PostgreSQL ODBC drivers are here. Info on the connection string format can be found here.
Here's an example of what pgAdmin looks like:
I'm not sure if used the right terminology in my question but here's what I'm trying to do. From the command line, I am used to running the following command :
psql -U postgres
and then I can see a list of all my databases by doing:
postgres=# \l
I'm wondering how to do the same thing programmatically in lua?
The following function is what I currently use to connect to a specific db:
local db_env, db_con
local connect_db = function()
if not con then
db_env = assert (luasql.postgres())
db_con = assert (db_env:connect(databasename, databaseUser, databasepassword))
end
end
Just wondering how I would change it to connect to the instance of postgresql server to see all the dbs that are hosted by my server.
Thanks.
Edit 1
Perhaps when I'm running the command
psql -U postgres
it is connecting to a default database?
In your code you have to connect to the database server and query the server for a list of databases. The database will return a recordset containing a list of the databases on that server.
A great walk-through of connecting to postgres and executing queries ( like the one above that hjpotter92 posted).
Hitting Postgres From Lua
Hope you find it helpful
I got this error from an Play 2.0.3 java application. How could I restart Heroku Postgres Dev DB? I could not find any instructions to restart the DB on Heroku help center.
app[web.1]: Caused by: org.postgresql.util.PSQLException: FATAL: remaining connection slots are reserved for non-replication superuser connections
The error mesage you have there isn't a reason to restart the database; it isn't a database problem. Your application is holding too many connections, probably because you forgot to set up its connection pool. That isn't a DB server problem and you can fix it without restarting the DB server.
If you stop your Play application or reconfigure its connection pool the problem will go away.
Another option is to put your Heroku instance in maintenance mode then take it out again.
Since heroku doesn't allow you to connect as a superuser (for good reasons) you can't use that reserved superuser slot to connect and manage connections like you would with normal PostgreSQL.
See also:
Heroku "psql: FATAL: remaining connection slots are reserved for non-replication superuser connections"
http://wiki.postgresql.org/wiki/Number_Of_Database_Connections
If you're a non-heroku user who found this:
With normal PostgreSQL you can disconnect your client from the server end end using a PostgreSQL connection to your server. See how it says there's a slot reserved for "superuser connections" ? Connect to Pg as a superuser (postgres user by default) using PgAdmin-III or psql.
Once you're connected you can see other clients with:
SELECT * FROM pg_stat_activity;
If you want to terminate every connection except your own you can run:
SELECT procpid, pg_terminate_backend(procpid)
FROM pg_stat_activity WHERE procpid <> pg_backend_pid();
Add AND datname = current_database and/or AND usename = <target-user-name> as appropriate.
I think I should have just added this in reply to the previous answer, but I couldn't figure out how to do that, so...
As an update to Liron Yahdav's comment in the accepted answer's thread: the "non-heroku users who found this" solution worked for me on a Heroku PostgreSQL dev database, but with a slight modification to the query Liron provided. Here is my modified query: SELECT pid, pg_terminate_backend(pid) FROM pg_stat_activity WHERE pid <> pg_backend_pid() AND usename='<your_username>';
It seems that procpid has changed to pid.
There is no way to restart the whole database. Though, heroku offers a simple way to stop all connections which solves the problem in the majority of cases:
heroku pg:killall