Microsoft Access is a convenient database package. It has templates for creating personal databases for books, recipes, etc. These templates are accessed by the Database Wizard which can be opened from the initial screen. The more specialized databases are created using

It is important to note that a database file must be created at the beginning because the database tables containing the information for the database can only be stored in such database files, which have the extention .mdb. Otherwise, you may find that you enter the data in a table but because you have no .mdb file to store it in it will be lost.

It is probably most efficient to enter the data into an Excel file and then import that file into Access. One reason that it is more convenient to work through Excel is that arithmetic manipulations such as computing ratios are easily done in Excel but only done with difficulty or not at all in Access.

There is at least one feature that may make it worth the extra effort to enter the data directly into a database table in Access. Access allows one to specify the exact nature of the data for a particular variable (column) and will thus prevent the entry of data that goes beyond the allowed range. For example, suppose that some variable must be a percentage between 0 and 100. Once that condition, called a validation rule in Access, is specified then Access will refuse to accept an entry of a negative number or a number larger than 100. Also if a datum is not available then a NULL value may be entered and Access will not treat that NULL entry as a zero but will carry out operation properly taking into account that that item is missing.

Thus one should go through the process of "designing" the database. This includes specifying the nature of the variables and giving the column headings. In particular, if you do not tell Access that a column of data is numerical it will, by fault, treat it as text even though all the characters are digits. You indicate that the type of a variable is Number in the design view by clicking on the table cell that gives the type of the variable as Text. At the right of the cell a square appears with a black triangle. When you click on the black triangle a list of data type appears and you can scroll down to the entry, Number and click. That enters Number as the type of the variable.

Once the data is entered into the database the operations of sorting and selecting subtables from the data can be carried out.

Retrieving information from a database involves generally the creation of subtables.

Creation of Subtables by Means of Queries

• Open Database using File/Open
• After the database is open there is a window showing tabs for Tables | Queries | Both | Forms | Reports | Macroes | Modules.
• Select QUERIES
• Deselect any queries that may be highlighted by clicking on blank space
• Click on NEW
• With DESIGN VIEW highlighted click on OK
• Click on the tab for Tables
• Highlight the table you want to work with
• Close the window for Show Tables
• Suppose the data table contains the name of provinces and their population and area
• Type in the name of field and click on the checkbox to have that field displayed
• If you want all the provinces with population densities greater than 1000 then into the field row for the second column POPULATION/AREA and into the criteria row >1000
• Click on the x at the upper-right corner and ACCESS will ask you if you want to save the changes
• Click on SAVE
• Now the query can be opened to see the results
• The query in the form of SQL can be viewed by selecting VIEW and clicking on SQL VIEW

Importing a database from Excel

• First create the Microsoft Database file, .mdb
• Select FILE and click on GET EXTERNAL DATA
• Select IMPORT
• Scroll down the File Type menu to Microsoft Excel files
• Select from the list provided the file to be imported
• Click on IMPORT
• Click on NEXT
• Click on FINISH