FireDAC.MSAccess Sample

This sample demonstrates how to use FireDAC to work with MS Access databases.

Location

You can find the MSAccess sample project at:

• Start | Programs | Embarcadero RAD Studio Sydney | Samples and then navigate to:
  • Object Pascal\Database\FireDAC\Samples\Getting Started\MSAccess
• Subversion Repository:
  • You can find Delphi code samples in GitHub Repositories. Search by name into the samples repositories according to your RAD Studio version.

Description

The MSAccess getting started sample shows how to use FireDAC with MS Access databases. This application sample provides the following features to the user:

• Temporary connection definition at run time.
• Master-details relationship between datasets using TFDQuery.
• Management of MS Access databases, such as: creating and compacting a database.

How to Use the Sample

1. Navigate to the location given above and open GettingStarted.dproj.
2. Press F9 or choose Run > Run.
3. Click on the Connection combo box and select <Open database…>. Open the following database: C:\Users\Public\Documents\Embarcadero\Studio\17.0\Samples\data\FDDemo.mdb.
4. Interact with the sample.

Files

File in Delphi	Contains
GettingStarted.dproj GettingStarted.dpr	The project itself.
fGettingStarted.pas fGettingStarted.fmx	The main form.

Implementation

The sample implements the following features:

Creating Temporary Connection Definition

The simplest way to configure connection to MS Access database at run time is to build a temporary connection definition:

with dbMain do begin
  Close;
  // create temporary connection definition
  with Params do begin
    Clear;
    Add('DriverID=MSAcc');
    Add('Database=x:\path_to_db\db.fdb');
  end;
  Open;
end;

In the sample, the temporary definition is created when the <Open database…> item is selected in the Connection combo box.

Master Details

In the demo database, the Categories and Products tables have one-to-many relation by CategoryID field. The qryCategories.SQL property is set up as follows:

select * from Categories

In addition, the qryProducts.SQL property is set up as follows:

select * from Products
where CategoryID = :CategoryID

Finally, the qryProducts.MasterSource property is set to dsCategories, while the MasterFields property is set to CategoryID. This creates a master-details relationship between the datasets.

Executing Queries

Simple queries execution is demonstrated via ExecSQL method of TFDConnection.

Inserting a record providing parameters of various types:

dbMain.ExecSQL('insert into Categories(CategoryName, Description, Picture) ' +
               'values(:N, :D, :P)', ['New category', 'New descr', $0334]);

Updating records:

 dbMain.ExecSQL('update Products set UnitPrice = UnitPrice * :P1 + :P2 ' +
                'where ProductID < 3', [Random(5), Random(3)]);

Deleting a record:

dbMain.ExecSQL('delete from Categories where CategoryName like :N', ['New category']);

Getting a scalar value from the database:

iID := dbMain.ExecSQLScalar('select MAX(CategoryID) from Categories');

Management of MS Access database

The management of databases, such as: creating, dropping, compacting/repairing, and setting a password is done using TFDMSAccessService component.

This demo demonstrates how to create and compact the user database:

with accService do begin
  Password := 'p@ssword';
  Database := 'x:\path_to_database\db.mdb';
  CreateDB;
end;
…
with accService do begin
  Password := 'p@ssword';
  Database := 'x:\path_to_database\db.mdb';
  Compact;
end;

Uses

• TFDQuery
• TFDConnection
• TFDMSAccessService
  • CreateDB
  • Compact

See Also

• Defining Connection (FireDAC)
• Connect to Microsoft Access Database (FireDAC)
• Master-Detail Relationship (M/D)
• Mobile Tutorial: Using FireDAC and SQLite
• MS Access Questions (FireDAC)

Samples

• FireDAC InterBase sample
• FireDAC MS SQL sample
• FireDAC MySQL sample
• FireDAC SQLite sample
• FireDAC Firebird sample