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Questions tagged [database-connection]

A database connection is a facility that allows client software to communicate with database server software, whether on the same machine or not. A connection is required to send commands and receive answers.

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What is the format for the PostgreSQL connection string / URL?

What is the format for the PostgreSQL connection string (URL postgres://...) when the host is not the localhost?
JII
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MySQL Error: : 'Access denied for user 'root'@'localhost'

Consider: ./mysqladmin -u root -p** '_redacted_' Output (including typing the password): Enter password: mysqladmin: connect to server at 'localhost' failed error: 'Access denied for user 'root'@'localhost' (using password: YES)' How can I fix…
Harsh Trivedi
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Cannot Connect to Server - A network-related or instance-specific error

I get the following error when trying to connect to SQL Server: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is…
Sasa Shree
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How to list active connections on PostgreSQL?

Is there a command in PostgreSQL to select active connections to a given database? psql states that I can't drop one of my databases because there are active connections to it, so I would like to see what the connections are (and from which…
Tregoreg
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Warning about SSL connection when connecting to MySQL database

With the two classes below, I've tried connect to a MySQL database. However, I always get this error: Wed Dec 09 22:46:52 CET 2015 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL…
Milos86
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How do I manage MongoDB connections in a Node.js web application?

I'm using the node-mongodb-native driver with MongoDB to write a website. I have some questions about how to manage connections: Is it enough using only one MongoDB connection for all requests? Are there any performance issues? If not, can I setup…
Freewind
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PG::ConnectionBad - could not connect to server: Connection refused

Every time I run my rails 4.0 server, I get this output. Started GET "/" for 127.0.0.1 at 2013-11-06 23:56:36 -0500 PG::ConnectionBad - could not connect to server: Connection refused Is the server running on host "localhost" (::1) and…
fadelakin
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How to connect to SQL Server database from JavaScript in the browser?

Can anybody give me some sample source code showing how to connect to a SQL Server 2005 database from JavaScript locally? I am learning web programming on my desktop. Or do I need to use any other scripting language? Suggest some alternatives if you…
Enjoy coding
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How does spring.jpa.hibernate.ddl-auto property exactly work in Spring?

I was working on my Spring boot app project and noticed that, sometimes there is a connection time out error to my Database on another server(SQL Server). This happens specially when I try to do some script migration with FlyWay but it works after…
METTAIBI
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MSSQL Error 'The underlying provider failed on Open'

I was using an .mdf for connecting to a database and entityClient. Now I want to change the connection string so that there will be no .mdf file. Is the following connectionString correct?