The Tables of a Database


Introduction to Tables

The table is the most fundamental object is a database. It is used to organize a list of values. The values can be as simple as some numbers: 2, 934, 6, 7547, and 85. The list can be made of names of people: Rodney, Helene, Scott, Nicolas, and Patricia. The list can be made of apparent insignificant items: RDX, S4, TL, M6, QX56, and 9-7X. The first rule is all items should be of the same type.

To make the list more elaborate, each item can be made of different values. Here is an example:

Manufacturer Model Year Value
Acura RDX 2007 34500
Audi S4 2004 31860
Acura 2002 14750
BMW M6 2006 76600
Infiniti QX56 2006 36580
Saab 9-7X 2005 42040

The Categories of Values or Columns of a Table

To make it easy to recognize its items, a table organizes its values each in a category. In the above table, the categories are Manufacturer, Model, Year, and Value. In a table, category is also called a column, probably because it displays vertically.

Each category starts on top with a a column header that can be considered its name. Because this string indicates the purpose of the columns, it is also referred to as its caption.

The Records of a Table

Under each column, there is a series of values aligned vertically. A series of horizontal values corresponding to each column is called a record. In the above table, the first record has the values Acura, RDX, 2007, and 34500. This group of values is called a record.

As you can see, a table can have as many records as necessary. Here is an example:


Table Layout: The Table's Tab

A table is presented as a rectangular window represented in the middle of the screen with a tab. As an option, you can remove the tabs and let the tables display without them. To do this, you can click the Office Button and click Access Options. In the left frame, click Current Database and, in the right frame, in the Document Window Options section, click the Tabbed Documents radio button and remove the check mark on the Display Document Tabs check box:

Access Options

After making the selection, you can click OK. You will be asked to close and reopen the database:

Which you should do.

On the left side of its top section, a table presents an icon Table Icon . The table icon provides a menu you can access when you right-click. The menu allows you to save or change the view of the table.

When a table displays with a tab, the extreme right section of the tab(s) shows a close button Close you can click to close the table.

The Table System Buttons

In Microsoft Office Access 2007, by default, a table in Datasheet View is represented with a tab, which prevents the user from moving it around. If you want, you can make the tables of a database appear as single documents. To do this, open the Access Options dialog box from the Office Button and click. In the left frame, click Current Database. Under Document Window Options in the right frame, you can click the Overlapping Windows radio button before clicking OK:

You will be asked to close and reopen the database.

A Table as a Datasheet

Although a table is primarily recognized as an arranged list of columns and rows, each column and each row intersect to create a rectangular box called a cell:

The cell is actually the object that holds data of a table. A cell holds only one piece of information. The database developer decides what type of information would go into a cell but the user types that information. Based on its arrangement of cells, a table is said to display in a datasheet layout or simply a datasheet (because its view is made of cells).

The Scroll Bars

If you start entering data into a table and there are more records than the height of the table can display, the table would be equipped with a vertical scroll bar. The vertical scroll bar would allow you to move up and down on the datasheet. This is useful if/when a table has more records than can be displayed all at once, and this will happen regularly. In the same way, if a table contains one or more records than the width of the table can display, the table would be equipped with a horizontal scroll bar:

Scroll Bars

The presence or absence of one or both scroll bars is automatically managed by the operating system and you should not be concerned with the management of the scroll bars. At the same time, if your users need to use a table, they know how to use a scroll bar.

Table Navigation Buttons

The lower left side of the table is made of four buttons used to navigate the table, one button used to create a new record, and a text box. Each button plays a specific role:

Button Name Role
First Record Allows moving to the first record of the table
Previous Record Allows you to move one record back (if there is one) from the current record
Current Record Displays the number representing the current record out of the total number of records
Next Record Allows moving you one record ahead
Last Record Allows moving you to the last record of the table
 New (Blank) Record Used to enter a new record on the table



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