Lesson 01: Introduction to Microsoft Access and VBA

	Introduction to Microsoft Access and VBA

Databases and Libraries

Introduction

A database is a list of items stored somewhere to make their values easy to access or retrieve. This means that a database can exist anywhere, including human or non-human memory. A computer database is a list or a group of lists created as a project. There are various ways and various types of applications used to create such a list. To make it more useful, special computer applications are formally developed to help create and manage computer databases.

Microsoft Access is an application used to create computer databases that can be used on a Microsoft Windows operating system, on a web site, or on a portable medium.

Various Libraries for a Database

Because there are many requirements and many options for computer databases nowadays, there are also various techniques of creating a database. Still, by its basic definition, a database is primarily one or more lists. How the list(s) is (are) created can depend on various circumstances. To make it possible to create databases, various libraries have been developed and you use one of these libraries to do a better job:

Microsoft Access Object Library: Microsoft Access provides its own mechanism for creating and managing a database. It provides most of the tools you need to start and complete a database project. Microsoft Access is also equipped with a library, the Microsoft Access Object Library that you can use to programmatically create and manage databases. This library is already available to you so you don't have to "load" it.

Microsoft Data Access Object: Microsoft Data Access Object, or DAO, is a library that ships with Microsoft Access and allows you to create, maintain, and manage databases. It also provides various means of performing the necessary operations on a database.

Microsoft ActiveX Data Objects: Microsoft ActiveX Data Objects, also called ADO, is a library that was developed to allow programmers with other environments to create and manage Microsoft Access databases. To support this, it provides a driver that allows these other programming environments to "attach" their applications to a Microsoft Access database. Like Microsoft Access' own library, you can use ADO inside of Microsoft Access to fully create and manage a database.

Microsoft ADOX: Microsoft ActiveX Data Object Extensions for Data Definition Language and Security, also called ADOX, is an addition to ADO. Besides many of the ADO operations it can perform, you can use it for additional assignments such as creating a database.

ADO.NET: ADO.NET is a technique developed by Microsoft and that is part of the .NET Framework. This technology allows you to use one or more libraries of the .NET Framework and one or more of the languages of the .NET Framework to create and manage a database. Although its name includes ADO, ADO.NET is neither ADO nor a real library, it is a technique of creating and managing databases. For example, while ADO contains objects and collections, ADO.NET does not own anything (because it is not a library; it is only a concept of dealing with databases).

Win32 API: A library is practically never complete. To complement those cited above, you can use others. One the external libraries you can use is called Win32. It belongs to Microsoft Windows and is already installed with the operating system. Because most of its functions are written in C, they cannot be directly used in a Microsoft Access database: you must import them.

Other Libraries: Besides the above libraries, Microsoft and other companies regularly publish other libraries you can use to perform some tasks in your Microsoft Access databases. Additionally, you can also create your own library, or ask someone else to create libraries for you, using languages such as C, C++, Pascal, etc.

Microsoft Access

Introduction

In our lessons, we will use Microsoft Office Access 2010 to create computer-based databases. Probably the easiest technique to launch Microsoft Access consists of clicking Start -> (All) Programs -> Microsoft Office -> Microsoft Office Access 2010.

Practical Learning: Starting Microsoft Access

Start Microsoft Access

Microsoft Access Databases

Introduction

There are various types of databases you can use in Microsoft Access. You can create a database from scratch. You can use some objects that ship with Microsoft Access 2010 to create a database. You can open either a database you previously created or one made by someone else.

Visually Creating a Microsoft Access Database

There are various ways you can create a database. To visually start a database from scratch, after launching Microsoft Access, you can click Blank Database. In the right section, accept or change the name of the database. If you want to create a Microsoft Access 2010 database, either omit or add the .accdb extension. If you want to create a database that is compatible with previous versions of Microsoft Access, you must add the extension .mdb.

After specifying the name, to specify a folder of your choice, under File Name and on the right side of the name of the database, click the Browse button . This would open the File New Database dialog box. You can click the arrow of the Save In combo box to select a drive such as (A:), (C:), etc. After selecting the drive, you can either select an existing folder or create a new folder by clicking the Create New Folder button on the right side of the Save In combo box. You can also use a directory on the network as the repository of the new database.

After specifying a drive and a folder, you can click Create.

Creating a Database Using a Wizard

Microsoft Access ships with a few sample databases you can use and customize. To create a database from a template, after launching Microsoft Access, in the middle section, locate one under Available Templates:

Available Templates

Click one of the buttons. Access or change the suggested name of the database, and click Download.

Deleting a Database

If you have a database you do not need anymore, you can delete it. To delete a database, in My Documents, in Windows Explorer or another file management application:

You can click it to select it and press Delete
You can right-click it and click Delete

A warning message would be presented to you to confirm what you want to do.

After you have deleted a database, it doesn't disappear from the MRU lists of Microsoft Access. This means that, after a database has been deleted, you may still see it in the left list of the Microsoft Access interface. If a database has been deleted and you want to remove it from the MRU lists, open the Registry (Start -> Run: regedit, Enter) and search (F3) for its name. It may be located in:

HKEY_CURRENT_USER
    - Software
      - Microsoft
        - Office
          - 12
            - Access 
              - Settings

Locate the deleted database and delete its key.

Microsoft Visual Basic Fundamentals

Introduction

Most of the time, you can create a good performing database using only Microsoft Office Access 2010. In some other cases, to create a more complex database, you would have to write code. To support this, Microsoft Access ships with, and installs, a programming environment named Microsoft Visual Basic. This is a variant of the popular Microsoft Visual Basic with everything you need to write code to complete your application.

In order to access Microsoft Visual Basic, you must first create or open a database in Microsoft Access. Then, on the ribbon, you can click the Database Tools tab. In the Database Tools section, you can click the Visual Basic button . This would open Microsoft Visual Basic:

Microsoft Visual Basic

As an alternative, in the Create tab of the ribbon, in the Macro & Code section, you can click either the Module or the Visual Basic button.

Practical Learning: Opening Microsoft Visual Basic

On the Ribbon, click Database Tools
Click the Visual Basic button

VBA and Macros

Visual Basic Child Windows

Almost any section of Microsoft Visual Basic is dockable, which means it can be moved on the screen to another location.

The Project window displays the coding objects available for your database. If the Project Explorer is not displaying, on the main menu, you can click View -> Project Explorer.

The Project window is usually on the left of the window. To move it, you can click its title bar under the Standard toolbar, hold your mouse down and drag to the desired location. To position it back to its previous location, you can double-click its title bar. To expand or collapse the folders tree, click the Toggle Folders button.

Every object and item of your database has characteristics, called properties, associated with it. You control those properties when you design the object. For example, when you are designing a form in Microsoft Access, you define what its caption would be. You can as well have access to these properties in Microsoft Visual Basic. These properties are displayed in the Properties Window when the object is selected.

Since the Project window and the Properties Window usually share the same section of the window (it is better that way), you can shrink one and heighten the other. To do that, position the mouse on the gray bar between both windows. When the mouse pointer turns into a short line with double arrows, click and drag.

The Code Editor is the area where you will mostly be working, this is the largest section of the Visual Basic Editor. It is mainly made of three sections:

On top, there are two combo boxes. To know the name of a combo box, you can position the mouse on it and a tool tip would come up:

The Object combo box allows you to select a particular object and access its events, actions that the object can launch. The Procedure combo box allows you to select an action, related to the object in the Object combo box, that you want to control.

The big and wide area is where you will be writing code. There are one vertical and one horizontal scroll bars that allow you to move left, right, up, and down in case your code is using more space than the Code Editor can display.

The Code Editor uses default colors to show the code. To customize these colors, you can use the Editor Format property page of the Options dialog box that you can access from the Tools -> Options... on the main menu:

There are two small buttons on the left side of the horizontal scroll bar. The Full Module View button is used to display the whole associated with an object. The Procedure View button will display only the public procedures associated with the database.

The Immediate window is used to test code when necessary. To display it, on the main menu of Microsoft Visual Basic, you can click View -> Immediate Window

Practical Learning: Using Microsoft Visual Basic Windows

To display the immediate window, on the main menu of Microsoft Visual Basic, click View -> Immediate Window
To use it, in the Immediate window, type ?now and press Enter
To return to Microsoft Access, on the Standard toolbar, click View Microsoft Access

Closing Microsoft Access and Visual Basic

The version of Microsoft Visual Basic we are using here is "For Applications". Indeed, you can create a fairly functional application with this version, but it is related to Microsoft Access. When you are in the Code Editor of Microsoft Visual Basic, you can get back to Microsoft Access either from the View Microsoft Access button on the Standard toolbar, or by clicking a Microsoft Access object on the Taskbar. The shortcut to get back to Microsoft Access is Alt + F11.

You can close Microsoft Visual Basic any time and keep Microsoft Access running. To do this, on the Standard toolbar of Microsoft Visual Basic, you can click the View Microsoft Access button to get back to the database. On the other hand, if you close Microsoft Access, Microsoft Visual Basic will be closed also.

Since Microsoft Access shares the same functionality you are probably familiar with from using other applications, you can close it easily.

To close Microsoft Access, you can click the Office Button and then click Exit Access
To close Microsoft Access from its title bar, you can click its Close button
To close Microsoft Access like any regular window of the Microsoft Windows applications, you can press Alt + F4
To close Microsoft Access using mnemonics, you can press Alt, F, X

Practical Learning: Ending the Lesson

To close Microsoft Access, click File -> Exit