New to ClickHouse, can't create local host - clickhouse

I'm new to clickhouse and trying to get started. I've installed all the packages needed to be able to use it on my computer (ubuntu 16.04) but when I use the clickhouse-client command I get the following:
ClickHouse client version 20.3.4.10 (official build).
Connecting to localhost:9000 as user default.
Code: 516. DB::Exception: Received from localhost:9000. DB::Exception: default: Authentication failed: password is incorrect or there is no user with such name.
Do anyone know what I should do?

Find the Password here:
Open the terminal and run:
sudo nano /etc/clickhouse-server/users.d/default-password.xml
Source : https://clickhouse.tech/docs/en/operations/configuration-files/

That's because the first time you installed ClickHouse you have entered the default password so you must provide that one as an argument to the clickhouse-client e.g
clickhouse-client --password=your-password
reference

Related

SQLPlus is throwing client hostname issue ORA-24454, whereas I can telnet to hostname successfully

I'm trying to connect to the oracle database via sqlplus hosted on a remote instance using command like this sqlplus user#hostname.com:port/SchemaName. And on typing password it throws weird client host issue. See the screenshot below.
The question is which host name its expecting me to put inside /etc/hosts?
Whereas I can telnet successfully to same instance without any issues. By the way I'm on MacOS 10.15.7.
Oracle clients were installed using this link. Can be seen from the screenshot below.
The installation was moved to the appropriate folder.
The $PATH was also exported to ~/.bash_profile file
I was able to resolve this issue by the solution mentioned on this link.
Using hostname command I was able to find host name of my machine, which was required to make a successful connection to the Oracle.
The screenshot below explains the process
The hostname entry looks like below

clickhouse-client get error "Timeout exceeded while reading from socket"

I'm newbie to clickhouse, I'm trying to create a clickhouse database on my unbuntu 18.04 remote server, I follow instruction to install click house from DEB package in this link: https://clickhouse.tech/docs/en/getting_started/install/#from-sources
after that when I run command clickhouse-client it shows something like this :
root#busmap-api-test:~# clickhouse-client
ClickHouse client version 20.3.5.21 (official build)
Connecting to localhost:9000 as user default.
Code: 209. DB::NetException: Timeout exceeded while reading from socket (127.0.0.1:9000)
Can someone help me to figure out what is the problem and how I can solve it?
Thanks,
Follow these steps to resolve the issue:
check that clickhouse-server-service started
service clickhouse-server status
check the server logs to find the possible reason
cat /var/log/clickhouse-server/clickhouse-server.err.log
if occured the error 'Address already in use':
{} <Error> Application: Net Exception: Address already in use: [::1]:9000
{} <Error> Application: Net Exception: Address already in use: 127.0.0.1:9000
need to switch CH-server to any other port by editing tcp_port-param in /etc/clickhouse-server/config.xml-file:
..
<tcp_port>9032</tcp_port>
..
restart CH-server service:
service clickhouse-server restart
and connect this way
clickhouse-client --port 9032
I actually had this problem too but I got it working with the default port.
The setting should be this way if you want to connect remotely and be able to use the loopback from localhost.
<listen_host>::1</listen_host>
<listen_host>0.0.0.0</listen_host>
This allows the loopback method to work (i.e clickhouse-client no args) on localhost to connect through the IPV6 route, and the remote connection (i.e clickhouse-client -h <hostname>) through the IPV4 connection.
My original problem was that i only used <listen_host>0.0.0.0</listen_host> in my config which meant theclickhouse-client no args would not work on localhost. And I could not get both to work by adding <listen_host>127.0.0.1</listen_host>

FATAL: no pg_hba.conf entry for host when setting up blazer gem

My application uses the blazer gem for visualizing DB queries.
During the setup I've encountered the following error:
FATAL: no pg_hba.conf entry for host "111.22.33.44", user "blazer", database "my_db", SSL off
My application is hosted on EngineYard and uses PostgreSQL.
How can I find and modify the pg_hba.conf on EngineYard?
upd
I do have SSH access to EngineYard cloud.
Instance: General Purpose (M3) Large.
OS: EngineYard's Gentoo.
You can try the following steps. I've assumed that your DB name is my_db.
Connect to the instance via SSH (the link can be found on the EngineYard environment page)
Connect to the
database as superuser psql -U postgres -h localhost -d
my_db. If you don't have the password, check your database secrets here /data/my_db/current/config/database.yml
After connecting to DB identify location of hba file by typing SHOW
hba_file;
Quit psql by typing \q
Use previously identified path to open the hba_file file and add the missing user. E.g via vim sudo vim /db/postgresql/9.5/data/pg_hba.conf. Note the sudo command
The use should be added under # IPv4 postgres
user for 10.x with md5:
Connect to the database again
Reload the configuration via select pg_reload_conf(); command
After all steps are performed, Blazer queries should be accessible.

How can I solve "Got minus one from a read call" in oracle sql developer?

When I run the sql developer and set the all data,click the connect but i get this error:
Status : Failure -Test failed: IO Error: Got minus one from a read call
I am beginner in Oracle. How can I solve that error?
I use 64-bit Windows7 and oracle 12c.
In my case the error is connected to a problem about the client's (SQL Developer) ojdbc8 driver and the Oracle 19.3 docker container. The solution for me was to set a system property on the client -- you can do it within the JDBC connection string):
jdbc:oracle:thin:#tcp://host:port/service?oracle.net.disableOob=true
This is the thread that lead me to the answer.
The cause of the error is described here:
https://support.oracle.com/epmos/faces/DocumentDisplay?_afrLoop=357910144923387
You can also solve this problem by dissabling OOB on server side in the sqlnet.ora:
DISABLE_OOB=ON
Another workaround is to use the ojdbc7 driver.
Hope this helps some of us.
From your inputs in the dialog, you are using port 5500. That port is what is used for EM Express. It answers to HTTPs traffic only. So in this case the -1 error message means the protocol negotiation failed. SQLDEV is trying to talk SQL*NET to something listening for HTTPs.
The port you are looking for is 1521 if it wasn't altered. If it was check the $ORACLE_HOME/network/admin/listener.ora for the proper port number.
You need set "tcp.validnode_checking = no" or comment this parameter in sqlnet.ora file then restart listener on db server and test again.
Try it.
I got the same issue but following steps worked for me, it seems Gaurav also has shared it already:
1.Go to the folder where you have installed the database (Like: F:\app)
2.Here you will be able to see many folders, go to product\11.2.0("your databse version")\dbhome_1\NETWORK\ADMIN
3.find listener.ora file and open as text file
4.Check for the port number in that file
5.Now provide that port number while doing connection in sql developer.
Seems you have enabled ACL on the listener.
You can follow these steps to avoid the error:
1. Go to directory $ORACLE_HOME/network/admin
2. Modify sqlnet.ora file with following parameter:
tcp.validnode_checking = no
3. If you don't want to disable this, you can put the machine names as follows:
tcp.invited_nodes=(machine1, machine2)
3. Bounce the listener.
Hope that helps
Ensure the DB is up and running and you can connect locally AS SYSDBA to the database using Oracle binaries owner (usually oracle:oinstall Unix / Linux user). If it does not work, probably you encounter a different problem.
Check privileges of an Oracle file on Unix / Linux host where database is running:
cd $ORACLE_HOME/bin
ls -ltr oracle
-rwxr-xr-x 1 oracle oinstall 136803483 Mar 16 20:32 oracle
Change permissions as below:
chmod 6751 oracle
ls -ltr oracle
-rwsr-s--x 1 oracle oinstall 136803483 Mar 16 20:32 oracle
Most of the answers out there for this problem point to using the wrong PORT number in your connection options, or similar. In my case, after a couple hours of searching, the reason showed to be something else.
Mind which user you are using when starting Oracle listener. You should do it with the oracle user, not as root. Otherwise you end up with listener files being created as e.g. user deamon group root instead of user oracle group dba. This in turn leads to:
TNS-12555: TNS:permission denied
TNS-12560: TNS:protocol adapter error
TNS-00525: Insufficient privilege for operation
Linux Error: 1: Operation not permitted
To check whether this is the case, go to
/var/tmp/.oracle
and list all files (ls -la). If you find out some of the s#* files being created by a root-group user, stop the listener (lsnrctl stop), delete the above files as root and restart the listener as oracle user.
Unfortunately sqldeveloper doesn't show the full stack-trace when reading "Got minus one from a read call". I could find the problem thanks to switching to SQL-Squirrel.
In my case, I was given wrong host and port. I typed "tnsping yourServiceName" in command line in window 10. It returns a different host and port, then I used the correct one in sql developer and it worked.
In my case, it happened when I was using Docker with Oracle 19C.
The workaround is to find the listener.ora file, change 'PORT' and restart the container, ORACLE DB, listener.
It is presumed to be an error that occurred when the host tried to access TCP because it was already LISENT (HOST) by another process.
(When accessing Docker, consider that in most cases, you are accessing localhost.)
I changed the port to 1523, and all the problems were solved.
Try to do what the link , or check listener directory permission, or use command /dbhome/bin/relink all
Try
Connection name: HR_ORCL
Username: HR ,
Password: hr ,
Connection type : local,
Role: SYSDBA
Click on connect.
It will work.
Actually, It is not database specific issue. it is related to port value generated by database during your installation. To overcome on this issue, please follow below.
Go to the folder where you have installed the database (Like: F:\app)
Here you will be able to see many folders, go to product\11.2.0("your databse version")\dbhome_1\NETWORK\ADMIN
find listener.ora file and open as text file
Check for the port number in that file
Now provide that port number while doing connection in sql developer.
Hope it will resolve your issue.

psql: could not connect to server

The error in its entirety reads:
psql: could not connect to server: No such file or directory. Is the
server running locally and accepting connections on Unix domain socket
"/tmp/.s.PGSQL.5432"?
This is my second time setting up Postgresql via Homebrew on my Mac, and I have no clue what is going on. Previously, it had been working. At some point, I must've entered a command that messed things up. I'm not sure. Now, whenever I enter a SQL command from the command line, I receive the above message. I've run a command to check whether the server is running, and it apparently is not. If I attempt to start the server using
$ postgres -D /usr/local/pgsql/data
I receive the following error:
postgres cannot access the server configuration file
"/usr/local/pgsql/data/postgresql.conf": No such file or directory
I've uninstalled and reinstalled Postgresql via Homebrew, but the problem persists. I'm completely at a loss as to how to get this working. Any help would be appreciated.
your data directory is most likely wrong.
issue a "sudo find / -name "postgresql.conf" " on your terminal to see where your postgres file resides. Then, do an ls in the data directory. Use that in the -D option when starting postgres.

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