ConnectionString

A ConnectionString is a string used by an application to specify how to connect to a data source. It encodes the data provider, the location of the data source, and authentication details so a driver or framework can open a connection.

A connection string typically includes components such as the data source or server address, the database name, user credentials or a flag for integrated security, and optional parameters such as timeouts, encryption, and pooling settings.

Formats and conventions vary by platform. In .NET's ADO.NET, a connection string is a semicolon-delimited list of key=value pairs, for example: "Server=myServerAddress;Database=myDataBase;User Id=myUsername;Password=myPassword;". In JDBC, connections are defined by a URL such as "jdbc:sqlserver://myserver:1433;databaseName=myDataBase;user=myUsername;password=myPassword;". ODBC commonly uses a DSN or keyword-value pairs like "DSN=myDSN;".

Security and management: credentials are sensitive and should not be hard-coded; prefer integrated security or secure credential storage, encryption, and accessing credentials from configuration sources or environment variables. Use least-privilege accounts and connection pooling to improve performance and reduce resource usage.

See also: connection pooling, authentication, environment variables, configuration management.