Controls are the different elements that are used to ensure data is entered in a way that is acceptable for data maintenance and tracking. From text boxes to drop down lists, there are a number of different controls you can implement to keep your data clean.
If you don’t provide controls to your database, you can end up with some very messy looking data. Microsoft Access provides controls so that you can limit the kind of information and method of entering information in Access.
Many users actually prefer to have controls. It means they don’t have to worry about how they enter things like dates or totals. Access database maintainers love controls because it makes it easier to ensure the data is clean. When data entry is only accepted based on certain criteria, such as formatting or character length, it is easier to find issues and discrepancies.
Types of Controls
There are three primary types of controls.
- Bound controls are those that have a source in a table or query. They are typically used to show field values. Examples of bound controls are text boxes, name fields, pictures, or numbers.
- Unbound controls do not have a source for their data. They are used for displaying information, like a label that shows the form’s title.
- Calculated controls have a data source from expressions instead of fields. Use the expression to determine the value that you need returned. As the name suggests, Access will calculate the results based on what you specify.
Each of these controls has a different use that enhances the user experience.
Control layouts provide guides that ensure your controls are aligned on the page. This provides an aesthetically pleasing appearance. It also makes it easier for users to see what information they have filled out and where they are missing data. There are many different ways to set up your layouts. However, there are two primary configurations:
Tabular – Tabular control layouts have controls that are arranged based on columns and rows, similar to a spreadsheet. They usually have labels running along the top, like a table header row. They take up two sections of your report. Access will automatically set up your controls in this layout based on the following situations.
- A report is generated using the Reports group under the Create tab and clicking Report.
- A report is generated from the Reports group under the Create tab and clicking Blank Report. If you then drag any of the fields listed under Field List to the report, the tabular layout is applied.
Stacked – Stacked control layouts are arranged vertically. This is more closely associated with lists or paper forms where data is identified to the left and the empty fields appear to the right. Access will automatically set up your controls in this layout based on the following scenarios:
- A form is generated using the Forms group under the Create tab and clicking Form.
- A form is generated from the Forms group under the Create tab and clicking Blank Form. If you then drag any of the fields listed under Field List to the form, the tabular layout is applied.
When Controls Aren’t the Problem
There are some things that controls cannot do. If you find that your data has been corrupted (usually you can tell by incorrect values and formatting), you should contact a specialist to help you with Access corruption recovery. Improper formatting and values are typically a sign that something else more serious is wrong with your database.
Victor Ren is a data recovery expert in DataNumen, Inc., which is the world leader in data recovery technologies, including repair xls file problem and word recovery software products. For more information visit www.datanumen.com