QSqlErrorTypeConnectionError
QSqlErrorTypeConnectionError is an enumeration value within the Qt framework's SQL module, specifically part of the QSqlError class. It represents a specific category of error that can occur when attempting to establish a connection to a database. When a database operation fails due to issues with the connection itself, such as incorrect credentials, network problems, or an unavailable database server, the QSqlError object returned will often have its type set to QSqlErrorTypeConnectionError. This allows developers to programmatically distinguish between different kinds of database errors. By checking the error type, applications can implement tailored error handling routines, providing more specific feedback to the user or attempting appropriate recovery actions. For instance, if a connection error occurs, the application might prompt the user to re-enter their login details or inform them that the database server is currently inaccessible. Understanding and utilizing QSqlErrorTypeConnectionError is crucial for robust database application development in Qt.