Working with databases/Database queries/Simple queries

Working with Databases

Basic skills applicable to planning, creating and using an Access database.
An OP Online course from the National Certificate in Computing (Level 2) programme.

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Activity

Please note: the following tutorial will open in a new window/tab. When you have finished the tutorial, simply close the window/tab and you'll return to this page. Before you go on, please work through the following tutorial: Using Queries to Make Data Meaningful - Part 1

Creating a simple query

A query allows us to analyse data contained in our table. With a query we can:

• Retrieve only the particular records that we want
• Filter out (or hide) data that does NOT meet a criteria (value)

A query is based on the fields in a table and can contain all of the fields in the table or some of the fields. When designing a query, you would look at the brief to decide what you need to show.

A query can be saved and re-used.

For example, from this table we could create a query that:

• Produces a list of students in alphabetical order
• Sorts students by address
• Shows only students who have scored higher than 75% in their subjects
• Shows students who are missing exam marks.

Activity

Using our bookshop database, we’re going to step you through the process of creating a simple query that will show us all books that are hardcovers. Open your bookshop database In Office 2007 choose Create Tab ⇒ Other Group ⇒ Query Wizard In Office 2010 choose Create Tab ⇒ Queries Group ⇒ Query Wizard From the dialogue box, choose Simple Query Wizard The Tables/Queries dropdown menu shows us tables we can use to make our query with. In this case we have only one – Books. The Available Fields menu shows us the fields in the selected table that we can use. We use the > button to promote fields into the Selected Fields box. These selected fields are what will actually be used to make our query. Use the > button to promote the following fields from your table into the selected fields menu: Title Year published Author Paperback book Click Next. From the next box that pops up, choose Detail then click Next. Give your query the name QRY_Paperbacks. Click on Finish. You should end up with a screen that looks like the following picture: Don’t forget to save your database.

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