Page 144 - Computing E-Book Grade 6

The City School 2021-2022

6. Open and enter 5 random records of an employee in tblEmployees table. Here, on

the left-hand side of each record, you will see a little plus sign by default. When you
create a relationship, Access will automatically add a sub-datasheet to that table.

5.9. Queries in MS Access

Database tables can hold a lot of records, Checkpoint

in some cases, millions or billions of them.
Queries allow you to pull information from Not Null enforces that field
cannot be left unused.
one or more tables based on a set of Unique constraint enforces
that the data in the field
search conditions that you define. cannot be repeated.

A query is a special “question” you apply to the database to find specific data and get
the information you want. For this task, let’s continue working with the Employee table

we have used before.

Planning a Query

When planning a query that uses more than one table, you should go through these
four steps:

Pinpoint
Knowing precisely what question you want to answer is essential to building

a useful query.

Identify

Know every type of query result you want included in your query results.

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