Uisng Connection Provider

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Uisng Connection Provider

TMemTableEh - TXXXDataDriverEh - TXXXConnectionProviderEh

New components TXXXConnectionProviderEh provide a single point of connection to the database. TADOConnectionProviderEh for ADO, TDBXConnectionProviderEh for DBExpress etc.

for each method of data access component of your ConnectionProvider.

ConnectionProvider he does not join, but has built-in component InlineConnection (for ADO is TADOConnection, for DBExpress TSQLConnection, etc.) and additional properties, a reference to the standard data access component of the same type (for example if you want to lay TADOConnection separately on form).

In component TXXXConnectionProviderEh you also specify the type of server data (MSAccess, SQLServer, Oracle, InterBase, etc.). Some ConnectionProvider automatically determine the type of server (for example, TIBXConnectionProviderEh this will always be the server 'InterBase'). The type of server components defines additional parameters for the database server. For example, on the type of server component TXXXDataDriverEh defines the operating mode with auto increment fields. In TXXXConnectionProviderEh can specify different connection objects at the Design-Time and Run-Time, thereby dividing the ways you can connect to the database during development and in the period of the program. The component also allows you to specify access TADOConnectionProviderEh path to MSAccess database in Design-Time line relative file location.

A relative path starts from the location of the form file, which has a component TADOConnectionProviderEh.

For example:

ADOConnectionProviderEh1.InlineConnection.ConnectionString = 
'Provider = Microsoft.Jet.OLEDB.4.0;
Data Source =% PROJECT_PATH% \ ..\ Data \ DBTest.mdb; 
Persist Security Info = False '

When you open the form in Design-Time component replaces the macro % PROJECT_PATH% to the path where the dfm form file is. This allows you to move the project to different computer and at different location without changing the ways of access to the database file.

Demo: See Demo project using cords TMemTableEh-TADODataDriverEh-TADOConnectionProviderEh in your library - <EhLib Dir\Demos\DataDriver.ADO.SimpleDemo/>

Demo: See Demo project using cords TMemTableEh-TBDEDataDriverEh-TBDEConnectionProviderEh in your library - <EhLib Dir\Demos\DataDriver.BDE.SimpleDemo>

Demo: See Demo project using cords TMemTableEh-TDBXDataDriverEh-TDBXConnectionProviderEh in your library - <EhLib Dir\Demos\DataDriver.DBX.SimpleDemo>

Demo: See Demo project using cords TMemTableEh-TIBXDataDriverEh-TIBXConnectionProviderEh in your library - <EhLib Dir\Demos\DataDriver.IBX.SimpleDemo>

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Contributors: dmitrybv