Page 96 - Database-En-V3

Types of inquiries:

1) Select Query
It is considered one of the most common types. It is used to retrieve data from one

or more tables and displays the results on a data page. You can update a set of
records based on some constraints, or you can also use a select query to group
records and calculate totals and criteria. Standards, averages, and other types of
totals.
2) Action Query
An action query is a query that makes changes to many records in just one
operation. There are four types of action queries:
- Delete Query: It is used to delete a group of records from one or more tables.
For example, you can use a delete query to remove records for graduating students
from the Students table. Note that with delete queries, you can always delete entire
records, not just specific fields within records.
- Update Query: An update query makes global changes to a set of records in one

or more tables. For example, you can increase each student who received a
score of less than 7 by five points to raise the averages they obtained. Using an
update query, you can change data in existing tables
- Append Query: An append query adds a set of records from one or more tables
to the end of one or more tables. For example, suppose a group of new students
has registered and their data is entered into a new table, you would append the
table containing the new student records to the Students table.
- Create-Table Query: This query is used to create a new table from all or part of
the data in one or more tables. Create table queries are useful for creating a
table to export to databases or a history table that contains old records.

3) Parameters Queries or Criteria Conditions:
When it runs, it displays its own dialog box asking you for information such as
specific criteria for retrieving records or a value you want to insert into a field.
You can design a conditional query to ask for more than one piece of
information; For example, you could design it to prompt you for two dates. In
this case, the database engine retrieves all records that fall between these two
dates. Parameter queries are convenient when used as the basis for forms,
reports, and data pages. For example, you can create a report on each student's
grades based on a parameter query. When you print the report, the database

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