Applications communicate with a database, firstly, to retrieve the data stored there and present it in a user-friendly way, and secondly, to update the database by inserting, modifying and deleting data.
This is integral to the working of ADO.Net since data is transferred to and from a database through a data adapter. It retrieves data from a database into a dataset and updates the database. When changes are made to the dataset, the changes in the database are actually done by the data adapter.
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DataSet is an in-memory representation of data. It is a disconnected, cached set of records that are retrieved from a database. When a connection is established with the database, the data adapter creates a dataset and stores data in it. After the data is retrieved and stored in a dataset, the connection with the database is closed. This is called the 'disconnected architecture'. The dataset works as a virtual database containing tables, rows, and columns.
It represents a row in the DataTable. The DataRow object and its properties and methods are used to retrieve, evaluate, insert, delete, and update values in the DataTable. The NewRow method is used to create a new row and the Add method adds a row to the table.
So far, we have used tables and databases already existing in our computer. In this example, we will create a table, add columns, rows and data into it and display the table using a DataGridView object.
Most of the properties you can set for DAO objects are DAO properties. These properties are defined by the Microsoft Access database engine and are set the same way in any application that includes the Access database engine. Some properties that you can set for DAO objects are defined by Microsoft Access, and aren't automatically recognized by the Access database engine. How you set properties for DAO objects depends on whether a property is defined by the Access database engine or by Microsoft Access.
To set a property that's defined by the Access database engine, refer to the object in the DAO hierarchy. The easiest and fastest way to do this is to create object variables that represent the different objects you need to work with, and refer to the object variables in subsequent steps in your code. For example, the following code creates a new TableDef object and sets its Name property:
When you set a property that's defined by Microsoft Access, but applies to a DAO object, the Access database engine doesn't automatically recognize the property as a valid property. The first time you set the property, you must create the property and append it to the Properties collection of the object to which it applies. Once the property is in the Properties collection, it can be set in the same manner as any DAO property.
The DBEngine is the highest-level object in the DAO object model. It contains all other objects and collections. The Database object is the member of the Databases collection of the default Workspace object, which is a member of the Workspaces collection of the DBEngine object.
DAO with JetMicrosoft Jet objects include TableDef, QueryDef, Field, Index, Parameter, Relation, Recordset, User, Group, Container, and Document. (See Figure B.)
To establish a connection using ODBCDirect, you have to use the OpenConnection method on a new Connection object or the OpenDatabase method to open a new Database object. A Connection object represents a connection to an ODBC database in an ODBCDirect workspace. The Connections collection contains all currently open Connection objects. When you open a Connection object, it is automatically appended to the Connections collection of the Workspace object. When you close a Connection object with the Close method, the Connections object is removed from the Connections collection.
Microsoft Access offers the functionality of a database and the programming capabilities to create easy to navigate screens (forms). It helps you analyze large amounts of information, and manage data efficiently.
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Many users find that using an external keyboard with keyboard shortcuts for Access desktop databases on Windows helps them work more efficiently. For users with mobility or vision disabilities, keyboard shortcuts can be easier than using the touchscreen, and are an essential alternative to using a mouse.
Use the keyboard shortcuts in the following sections to navigate to an insertion point within a field, copy, move, or delete text, and undo changes. You can also use your keyboard to enter data in the Datasheet View or Form View and refresh fields.
Microsoft wants to provide the best possible experience for all our customers. If you have a disability or questions related to accessibility, please contact the Microsoft Disability Answer Desk for technical assistance. The Disability Answer Desk support team is trained in using many popular assistive technologies and can offer assistance in English, Spanish, French, and American Sign Language. Please go to the Microsoft Disability Answer Desk site to find out the contact details for your region.
Microsoft Access is a database management system (DBMS) from Microsoft that combines the relational Access Database Engine (ACE) with a graphical user interface and software-development tools (not to be confused with the old Microsoft Access which was a telecommunication program that provided terminal emulation and interfaces for ease of use in accessing online services such as Dow Jones, Compuserve and electronic mailbox in the 1980s[3][4]). It is a member of the Microsoft 365 suite of applications, included in the Professional and higher editions or sold separately.
Microsoft Access stores data in its own format based on the Access Database Engine (formerly Jet Database Engine). It can also import or link directly to data stored in other applications and databases.[5]
Software developers, data architects and power users can use Microsoft Access to develop application software. Like other Microsoft Office applications, Access is supported by Visual Basic for Applications (VBA), an object-based programming language that can reference a variety of objects including the legacy DAO (Data Access Objects), ActiveX Data Objects, and many other ActiveX components. Visual objects used in forms and reports expose their methods and properties in the VBA programming environment, and VBA code modules may declare and call Windows operating system operations.
Microsoft's first attempt to sell a relational database product was during the mid 1980s, when Microsoft obtained the license to sell R:Base.[7] In the late 1980s Microsoft developed its own solution codenamed Omega.[8] It was confirmed in 1988 that a database product for Windows and OS/2 was in development.[9][10] It was going to include the "EB" Embedded Basic language,[8] which was going to be the language for writing macros in all Microsoft applications,[11] but the unification of macro languages did not happen until the introduction of Visual Basic for Applications (VBA). Omega was also expected to provide a front end to the Microsoft SQL Server.[12] The application was very resource-hungry, and there were reports that it was working slowly on the 386 processors that were available at the time.[13] It was scheduled to be released in the 1st quarter of 1990,[14] but in 1989 the development of the product was reset[7][15] and it was rescheduled to be delivered no sooner than in January 1991.[16] Parts of the project were later used for other Microsoft projects: Cirrus (codename for Access) and Thunder (codename for Visual Basic, where the Embedded Basic engine was used).[7][8] After Access's premiere, the Omega project was demonstrated in 1992 to several journalists and included features that were not available in Access.[17]
As a part of the Microsoft Office 4.3 Professional with Book Shelf, Microsoft Access 2.0 was included with first sample databases "NorthWind Trader" which covered every possible aspect of programming your own database. The Northwind Traders sample first introduced the Main Switchboard features new to Access 2.0 for 1994.The photo of Andrew Fuller, record #2 of that sample database was the individual that presented and worked with Microsoft to provide such an outstanding example database.
The native Access database format (the Jet MDB Database) has also evolved over the years. Formats include Access 1.0, 1.1, 2.0, 7.0, 97, 2000, 2002, and 2007. The most significant transition was from the Access 97 to the Access 2000 format; which is not backward compatible with earlier versions of Access. As of 2011[update] all newer versions of Access support the Access 2000 format. New features were added to the Access 2002 format which can be used by Access 2002, 2003, 2007, and 2010.
Microsoft Access 2007 introduced a new database format: ACCDB. It supports links to SharePoint lists and complex data types such as multivalue and attachment fields. These new field types are essentially recordsets in fields and allow the storage of multiple values or files in one field. Microsoft Access 2007 also introduced File Attachment field, which stored data more efficiently than the OLE (Object Linking and Embedding) field.
Microsoft Access 2010 introduced a new version of the ACCDB format supported hosting Access Web services on a SharePoint 2010 server. For the first time, this allowed Access applications to be run without having to install Access on their PC and was the first support of Mac users. Any user on the SharePoint site with sufficient rights could use the Access Web service. A copy of Access was still required for the developer to create the Access Web service, and the desktop version of Access remained part of Access 2010. The Access Web services were not the same as the desktop applications. Automation was only through the macro language (not VBA) which Access automatically converted to JavaScript. The data was no longer in an Access database but SharePoint lists. An Access desktop database could link to the SharePoint data, so hybrid applications were possible so that SharePoint users needing basic views and edits could be supported while the more sophisticated, traditional applications could remain in the desktop Access database. 2ff7e9595c
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