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Microsoft Access Ervin Ha
Content l l l l What is Microsoft Access Why use Access Limitations Basic background information Advanced features Example Conclusion
MS Access l l l Microsoft Program Part of the Microsoft Office suite Used to create relational database management system (RDMS) l l l consists of multiple tables, each storing specific information relates information from one table to another One-to-many relationships are the power behind a relational database Query the database to find information Enter information into forms Display results in reports
Why use RDMS l Facilitate information sharing l l Reduce data redundancy l l data can be queried from multiple tables joined and displayed in a subset of records the same data is not stored over and over again Keep data accurate l a change in data is made in one table but appears updated in all queries and reports
Why use MS Access l Easy to use l l Stand-alone l l Help File, Message boards Relatively cheap l l Do not require any other program to run or use Lots of support l l GUI, Looks good Comes with MS Office Suite Integration l Can be integrated with other MS Office applications
Limitations l It’s a Microsoft product l l Overly user- friendly l l Takes up lots of computer resources Expensive l l Tried too hard to predict what you what to do Not suited for large databases l l Bugs galore Must buy from Microsoft. Not open source Complicated to use for connectivity to other types of databases
Basics of Access l l The key window in Access is known as the ‘database window’. Seven objects can be launched from this window: l l l l Tables Queries Forms Reports Pages Macros Modules These objects, in turn, become their own windows.
Basics of Access l The smallest piece of information in a database is called a field l l A group of related fields is called a record l l customer name, address, phone number A table is a collection of records about a particular subject l l customer name customers A relational database consists of a set of related tables l Customers and Orders and Products
Basics of Access l Primary Key l l l Composite Key l l A field used to uniquely identify each record Every table in a database must have a primary key defined More than one field used in combination to uniquely identify each record Foreign Key l A field (in one table) that is related to a primary key in another table within the same database.
Basics of Access l Queries l l A subset of table information Similar to filter or find operation within table l l Also like a sort operation l l searches for records according to specified criteria and displays these records can change the order of records Differs from filter and sort in that a query can be run against several tables
Basics of Access l Forms l l l Used to easily view, enter, and change data directly in a table retrieves the data from one or more tables, and displays it on the screen also display pictures and other objects can contain a button that prints, opens other objects, or otherwise automates tasks Reports l Used to analyze your data or present it a certain way
Advanced Features l Microsoft Jet database engine l l l The part of the Access database system Retrieves and stores data in user and system databases. Thought of as a data manager upon which database systems, such as Access, are built.
Advanced Features l Open Database Connectivity (ODBC) l l l A standard method of sharing data between databases and programs. ODBC drivers use the standard Structured Query Language (SQL) to gain access to external data. Use to connect l l l Microsoft SQL Server databases Microsoft Fox. Pro databases other programs that provide 32 -bit drivers in compliance with ODBC Level 1 to access their data files (Oracle RDMS, Paradox, d. BASE, Lotus)
Advanced Features l Data Access Objects (DAO) l l A data access interface communicates with Microsoft Jet and ODBCcompliant data sources Used to connect to, retrieve, manipulate, and update data and the database structure. Enable you to manipulate the structure of your database and the data it contains from Visual Basic
Advanced Features l The following code creates a new Table. Def object and sets its Name property: Dim dbs As DAO. Database Dim tdf As DAO. Table. Def Set dbs = Current. Db Set tdf = dbs. Create. Table. Def tdf. Name = "Contacts"
Advanced Features l Connectivity l OLE DB l l A component database architecture provides efficient network and Internet access to many types of data sources relational data, mail files, flat files, and spreadsheets. Active. X Data Objects (ADO) l l manipulate the structure of your database and the data it contains from Visual Basic. Many ADO objects correspond to objects that you see in your database
Advanced Features l The following code creates a new Table. Def object and sets its Name property: Dim tbl As New ADOX. Table Dim cnn As ADODB. Connection Set cnn = Current. Project. Connection tbl. Name = "Contacts"
Example l Building from scratch l l l Staticfree Technology relationship diagrams Student Courses database Other examples l l FLI (Forms, Data entry) Bookstore (SQL queries, Reports)
Conclusion l Explained MS access l l Basics you need to know l l Keys, Tables, Queries, Forms, Reports Advanced features l l Relational Database Management System Jet Engine, ODBC, DAO, ADO, OLE Examples