I am trying to use a VM machine with R on Azure. I want to connect it to a mariaDB on Azure.
I use the RmySQL package, and I use the following connection string:
require(RMySQL)
con <- dbConnect(RMySQL::MySQL(),
dbname="energidb",
host="energidb.mariadb.database.azure.com",
port=3306,
user="USER",
password="MY_PWD")
However, No luck I have in trying this, as R says. "Error in .local(drv, ...) :
Failed to connect to database: Error: Unknown database 'energidb'"
On azure, I promise and guarentee with my life, the name of the mariaDB is "energidb"
What am I doing wrong?
If you just create a Maria DB resource on Azure portal, then you should only have a database server.
You can connect to the Maria DB without specifying a database name. And then list all the existing databases as following:
con <- dbConnect(RMySQL::MySQL(),
host="your host address, jackmariadb.mariadb.database.azure.com",
port=3306,
user="user name, jack#jackmariadb",
password="password, d*******5")
rs = dbSendQuery(con, "show databases")
fetch(rs, n=-1)
In my case, it will just show the 3 system databases:
It turns out that on Azure, I created a mariaDB server (without any database). The database reference i made was to the server, which ofcourse is meaningless.
The solution is first to create a database (which is done by pointing at the server). From there I can point on the database.
Related
I developed my app with SQLAlchemy testing it on an SQLite database.
Now I would like to testing more using PostgreSQL but in a localhost once again.
For this reason, I tried to create a local Postgre database with pdAdmin4 (my laptop has Windows 7 so I installed the v4 version of the database manager).
Now I am trying to generate the connection string for this Postgre database but I cannot understand how to do it.
This is what I created in pgAdmin4:
while the details of the server are these:
The connection string I am trying to use is this:
selected_engine = create_engine('postgresql+psycopg2://postgres:123#localhost/test_server/test_database')
The password 123 is the password I set at the first access to pgdAmin4.
However, I got this error:
OperationalError: (psycopg2.OperationalError) connection to server at "localhost" (::1), port 5432 failed: FATAL: database "test_server/test_database" does not exist
I am sure I am wrong and I cannot figure out what is the correct URL for my database.
I'm attempting to connect to a new Aurora PostgreSQL instance with Babelfish enabled.
NOTE: I am able to connect to the instance using the pg library through the normal port 5432 (the Postgres TDAS endpoint).
However, for this test, I am attempting to connect through the Babelfish TDS endpoint (1433) using the standard mssql package.
If I specify a database name (it is correct), I receive the error 'database "postgres" does not exist':
var config = {
server: 'xxx.us-east-1.rds.amazonaws.com',
database: 'postgres',
user: 'xxx',
password: 'xxx'
};
and the connection closes since the connection fails.
if I omit the database property in the config, like:
var config = {
server: 'xxx.us-east-1.rds.amazonaws.com',
user: 'xxx',
password: 'xxx'
};
It will connect. Also, I can use that connection to query basic things like SELECT CURRENT_TIMESTAMP and it works!
However, I can't access any tables.
If I run:
SELECT COUNT(1) FROM PERSON
I receive an error 'relation "person" does not exist'.
If I dot-notate it:
SELECT COUNT(1) FROM postgres.dbo."PERSON"
I receive an error "Cross DB query is not supported".
So, I can't connect to the specific database directly and if I connect without specifying a database, I can't cross-query to the table.
Any one done this yet?
Or, if not, any ideas on helping me figure out what to try next? I'm out of ideas.
Babelfish databases (that you connect to on port 1433) have nothing to do with PostgreSQL databases (port 5432). Essentially, all of Babelfish lives within a single PostgreSQL database (parameter babelfishpg_tsql.database_name).
You seem to have a single-db setup, because Cross DB query is not supported. With such a setup, you can only have a single database via port 1433 (apart from master and tempdb). You have to use CREATE DATABASE to create that single database (if it isn't already created; ask sys.databases).
I can't tell if it is supported to create a table in PostgreSQL (port 5432) and use it on port 1433 (the other way around is fine), but if so, you have to create it in a schema that you created with CREATE SCHEMA while connected on port 1433.
The answer was that I should be connecting to database "master".
Even though there is no database titled master in the instance, you still do connect to it.
Once connected, running the following:
select current_database();
This will indicate you are connected to database "babelfish_db".
I don't know how that works or why a database would have an undocumented alias.
The bigger answer here is that cross-DB object references are not currently supported in Babelfish, outside your current SQL Server database.
This is currently being worked on. Stay tuned.
I am running cadence with cassandra externally running using docker run -e CASSANDRA_SEEDS=10.x.x.x e ubercadence/server:. and its running sucessfully.
Azure cosmos says, any system running on Cassandra can use Azure cosmos using provided cosmos cassandra APi, by modifying the client connection creation code, for example : GO app sample code :
func GetSession(cosmosCassandraContactPoint, cosmosCassandraPort, cosmosCassandraUser, cosmosCassandraPassword string) *gocql.Session {
clusterConfig := gocql.NewCluster(cosmosCassandraContactPoint)
port, err := strconv.Atoi(cosmosCassandraPort)
clusterConfig.Authenticator = gocql.PasswordAuthenticator{Username: cosmosCassandraUser, Password: cosmosCassandraPassword}
clusterConfig.Port = port
clusterConfig.SslOpts = &gocql.SslOptions{Config: &tls.Config{MinVersion: tls.VersionTLS12}}
clusterConfig.ProtoVersion = 4
session, err := clusterConfig.CreateSession()
...
return session
}
From my end, I can connect external cassandra's cqlsh(which cadence is using for persisting) to azure cosmos and can create KeySpace, table in azure cosmo db.
However, when I run Cadence server, all new tables are still created on local cassandra itself(instead of Axure cosmos) might be, cadence is connected to cassandra only.
So there are basically 2 question shared below :
1.Since cadence is written in GO, can we modify the source code to establish connection to AzureCosmoDb.
or
or can we pass the cosmocassandra's host, port, username, password, while running the cassandra and cadence separately (docker run -e CASSANDRA_SEEDS=10.x.x.x e ubercadence/server:)
cosmosCassandraContactPoint : xyz.cassandra.cosmos.azure.com
cosmosCassandraPort : 10350
cosmosCassandraUser : xyz
cosmosCassandraPassword : xyz
I am actively working on supporting other NoSQL DBs: https://github.com/uber/cadence/issues/3514 it will be easier to use Azure cosmos/AWS Keyspace after that's done.
Basically we will just need to customize a small part from the existing Cassandra model.
I have trouble connecting to the Azure postgres database from python. I am following the guide here - https://learn.microsoft.com/cs-cz/azure/postgresql/connect-python
I have basically the same code for setting up the connection.
But the psycopg2 and SQLalchemy throw me the same error:
OperationalError: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
I am able to connect to the instance by other client tools like dbeaver but from python it does not work.
When I investigate in Postgres logs I can see that the server actually authorized the connection but the next line says
could not receive data from client: An existing connection was forcibly closed by the remote host.
Python is 3.7
psycopg's version is 2.8.5
Azure Postgres region is in West Europe
Does someone has any suggestion on what should I try to make it work?
Thank you!
EDIT:
The issue resolved itself. I tried the same setup a few days later and it started working. Might have been something wrong with the Azure West Europe.
I had this issue too. I think I read somewhere (I forget where) that Azure has an issue with the # you have to for the username (user#serverName).
I created variables and an f-string and then it worked OK.
import sqlalchemy
username = 'user#server_name'
password = 'PassWord!'
host = 'server_name.postgres.database.azure.com'
database = 'your_database'
conn_str = f'postgresql+psycopg2://{username}:{password}#{host}/{database}'
After that:
engine = sqlalchemy.create_engine(conn_str, pool_pre_ping=True)
conn = engine.connect()
Test it with a simple SQL statement.
sql = 'SELECT * FROM public.some_table;'
results = conn.engine.execute(sql)
This was a connection in UK South. Before that it did complain about the format of the username having to use #, although the username was correct, as tested from the command line with PSQL and another SQL client.
I am trying to get the React-fullstack seed running on my local machine, the first things I want to do is connect the server with a database. in the config.js file there exists this line:
export const databaseUrl = process.env.DATABASE_URL || 'postgresql://demo:Lqk62xgfsdm5UhfR#demo.ctbl5itzitm4.us-east-1.rds.amazonaws.com:5432/membership01';
I do not believe I have access to the account created in the seed so I am trying to create my own AWS PG RDS. I have the following information and can access more:
endpoint: my110.cqw0hciryhbq.us-west-2.rds.amazonaws.com:5432
group-ID: sg-1422f322
VPC-ID: vpc-ec22d922
masterusername: my-username
password: password444
according the the PG documentation I should be looking for something like this:
var conString = "postgres://username:password#localhost/database";
I currently have:
`postgres://my-username:password444#my110.cqw0hciryhbq.us-west-2.rds.amazonaws.com:5432`
What do I put in for 'database'?
Can someone share a method to ping the DB from the seed on my local machine to see if they are connected and working properly?
I can't really speak to anything specific to the React package, however generally when connecting to a Postgres server (whether RDS or your own install), you connect with the name of the database at the end of the connection string, hence:
postgres://username:password#hostname:port/databaseName
So, when you created the RDS database (I assume you already spun up RDS??), you had to tell RDS what you wanted to call the database. If you spun up RDS already, login to AWS console, go to RDS, go to your RDS instances and then select the correct instance, click "Instance Actions" and then "See Details". That page will show you a bunch of details for your RDS instance, one of which is "DB Name". That's the name you put in the connection string.
If you have not already spun up your own RDS instance, then go ahead and do so and you will see where it asks for a database name that you specify.
Hope that helps, let me know if it doesn't.