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Get an overview of Microsoft Access, covering relational databases, tables, queries, forms, reports, and other key objects. Explore data entry, storage, manipulation, and retrieval with Access. Learn about queries, forms, reports, and database object creation in Design View.
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Introduction to Microsoft Access Overview
Introduction • What is Access? • A relational database management system • What is a Relational Database? • A relational database system creates separate containers of logically related data, and stores each container in a separate table. • Tables are the key objects of a relational database • Tables form the basis for information storage and retrieval • A collection of tables that are related to one another form a database
Access Objects • Objects are the structures you create and methods you employ to store, manipulate and retrieve data • Objects include • tables • queries • forms • Reports • Pages (work with live data via the internet/intranet • Macros (start-up routines, Hot keys) • Modules (create apps within the database)
Tables • Data is entered into Tables • Tables hold all stored data • none of the other Access objects hold data. • Two dimensional • rows (records) • columns (fields/attributes of interest) • Row ordering is unimportant, • rows can be sorted and rearranged and not change the fundamental table information • Column ordering is unimportant, • A table column may be placed in any particular position
each column(field) holds a different characteristic (attribute) about the row (record) it describes the primary key – Attribute(s) that makes each row(record) unique
Queries • Data stored in tables can be filtered and sorted in queries • Data filtered and sorted by query can be displayed • Data filtered and sorted by query can be printed in reports
Query Types • Selection (projection) queries. • Select queries are the most common type. • They pose questions of the database and return answers in a dynaset(a virtual table) • Subsets of rows(records) are returned when selection criteria are specified to filter the data • All attributes for each record are also returned • Projection returns a subset of records and a subset of attributes for each record
Selection Query Selection Criteria
Action Queries • Alters(modifies) data in a table • Add data records to existing table from another table • Delete records in a table • Update records in a table • Creates new table using data from an existing table(s)
Forms • Provide a way to view table data one row at a time • Easier data entry • Easier data editing and modifications • Easier validation checks on entered data • Display data from tables or queries but do not actually hold data
Reports • Used to preview and print data for distribution • Provide formatted, hard-copy output • Displays database information that can be supplied by • tables, • queries, or • both • Can not be used to modify data
Creating Access Database Objects(tables, queries, forms, reports) • Design View • Create object from scratch • Wizards( forms, reports & queries) • Simplify initial creation of object • In many cases it is easier to use wizard to create the object, and make any modifications to the object created by the wizard in design view • Table Templates • Auto Form & Auto Report