Microsoft Access
Computing: Software: Microsoft Access
Microsoft Access is a software application that combines a database engine, a programming language (VBA) and IDE, and forms designed to allow easy display and editing of database records.
Related Pages
Bugs
The following applies to Access 97 and may not apply to later versions:
- Scroll Wheel Juggernaut Mode: If you accidentally move the scroll wheel while displaying a data form in single-record mode (i.e. not "continuous forms" mode), Access starts going through the records one by one until it gets to the first or last record (depending on which way you scrolled); this can take quite awhile, depending on the size of the recordset being displayed and the rendering time for each current record. It cannot be interrupted in any way, except by invoking the Windows Task Manager (ctrl-alt-delete) and killing the process for Access. Ctrl-C and Ctrl-Break have no effect.
- Lookup Lockup: If the query used to look up a value in a table view is too complex (e.g. includes a union), the table view will become "read-only".
Weaknesses
The following apply to Access 97 and may not apply to later versions:
- Although it is possible to write functions to translate source data into a different display format, it is not possible to write corresponding routines to translate user data-entry back into source data. It is not possible, therefore, for the user to edit data in a form or query if it has been manipulated in certain ways, including fields in queries above a certain level of complexity as well as any data which is the result of a function.
- Data from some sources (tentatively: queries of a certain complexity or higher, or possibly certain types of JOINs) cause data in continuous forms to be formatted improperly. The user has to manipulate the form in certain ways in order to restore the display.
- There are no tools for recovering data from a corrupted database file (.mdb)
- There appears to be a limit on the number of tables/queries which can be open simultaneously. This number is never stated outright, but if you try to open too many forms in an application written in Access, a message pops up saying "can't open any more databases", and some of the fields on the last form opened may be empty or display improperly.
Minor Annoyances
- Text formatting in stored Query objects is not preserved.
- There is no way to set the default view for new queries to SQL; you always have to go through several mouse-clicks to get from the default Design View to SQL View when creating a new query.
- You can't put comments inside query SQL, although you can edit descriptions for all object types (tables, queries, forms, etc.) and there is a display mode which will show the description next to each object.
Possible Bugs
UNION queries seem to return only unique rows; if this behavior is not desired, some kind of unique information needs to be included in the fieldset in order to prevent the collapse. (This is a tentative hypothesis based on one example only.) --Woozle 10:21, 23 May 2006 (EDT)
Some types of JOIN queries will refuse to update, claiming that validation rules are being violated -- even though the underlying tables have no validation rules set. When this error happens, Access needs to specify at least one field that is causing a problem, and how the validation rule is being violated. --Woozle 07:09, 10 November 2006 (EST)