Database Access

The Database Access Pattern consists of the following components:

Database Location Selection: allows the user to choose the database repository location he / she is going to work with. This can be done by means of a direct URL, or by displaying a list of available locations. In order for the list of available locations to be prepared, the history of previous user locations can be used.

Query History: allows the user to choose the query (in any form, e.g. query string) from a list of queries made in the past.
Query: it consists of two subcomponents:

Query Definition: allows the user to define / change the query which is submitted to the next subcomponent.
Query Submission: submits the query and displays a progress bar, if applicable

Query Result: allows the user to view the status of a finished query, to view error messages (if any) or view the query results (if applicable).

The entry point of the Database Access Pattern is always Database Location Selection. After the user successfully points to existing database he/she can start to define query. The user may choose from previously made queries or define new one. When the query preparation process is finished the user can submit the query and finally view the query results.