Chap 8 & 9 - Organizing and Manipulating Data in Databases and Database Forms and Reports Flashcards
What is a table and how is it useful?
It is a set of data elements (values) using a model of vertical columns (identifiable by name) and horizontal rows.
It is useful to store all of the records for a specific category.
What is a form in a database and how is it useful?
A form is a custom designed screen for entering records or displaying existing records
It is useful as a tool to enter data into a table or displaying data from a table.
What does cloud computing allow companies to do?
Expand their IT capabilities without investing in significant hardware, software, or training.
Benefits are low costs, scalability, and simplicity relative to creating in-house systems.
What is a data warehouse?
It is when data is pooled from separate applications into a large, common body of information.
How is a data warehouse useful?
- makes organizational information available on a corporate wide basis
- help businesses increase data-retrieval efficiency, output productivity and long term profitability
What is a report and how is it useful?
A report can be a simple document that displays the contents of a table (or query) or complex outputs that combine info from several tables and show selected subsets. Reports are strictly outputs.
Reports in access are mainly useful to create hardcopy outputs.
What is the total info in a database and the relationships between the tables called?
a schema
What is a query and how is it useful?
A query is a subschema that pulls selected records from selected tables to view a customized selection of data.
The info pulled using a query is called a dynaset.
What are 2 basic types of queries?
An action query = allows users to update or delete multiple records in a single operation
A select query = creates a dynaset of database info based on two types of user specified criteria: 1)criteria that determine which records to include and 2) criteria that determine which data fields to include FROM those records.
What is a primary key?
is a data field in each record that uniquely distinguishes one record from another in a database table
What is a relationship?
A relationship is the how one entity is related to another entity. Cardinality is how we describe how entities are related.
Why should tables be linked (or have relationships)?
to connect related fields through multiple tables
What is referential integrity?
It is a feature that controls certain inconsistencies among the records in relational tables.
If you try to delete a record that is linked to another table it will not let you.
