Register a Custom Schema Provider for a Synonym Database

• Mar 12, 2021
• 2 minutes to read

This document describes how to implement a custom data source schema provider that enables end-users to bind reports to a synonym database.

Tip

A synonym is a database object that provides an alternative name for another database object.

To learn about support for synonyms by different database engines, refer to the Oracle and Microsoft SQL Server documentation.

This document consists of the following sections:

• Implement a Custom Schema Provider
• Register the Schema Provider in a WinForms Reporting Application

Implement a Custom Schema Provider

The following code shows how to create a custom database schema provider inherited from the DBSchemaProviderEx class that is a default implementation of the IDBSchemaProviderEx interface.

C#

using DevExpress.DataAccess.Sql;
using DevExpress.Xpo.DB;
using System.Collections.Generic;
using System.Linq;
// ...

public class SynonymDBSchemaProvider : DevExpress.DataAccess.Sql.DBSchemaProviderEx {
    public override DBTable[] GetTables(SqlDataConnection connection, params string[] tableList) {
        List<DBTable> tables = base.GetTables(connection, tableList).ToList();
        if(connection.Name == "OracleConnection")
            tables.Add(new DBTable("Regions") {
                Columns = {
                    new DBColumn { Name = "REGION_ID", ColumnType = DBColumnType.Int32 },
                    new DBColumn { Name = "REGION_NAME", ColumnType = DBColumnType.String, Size = 25 },
                }
            });

        return tables.ToArray();
    }
}

VB.NET

Imports DevExpress.DataAccess.Sql
Imports DevExpress.Xpo.DB
Imports System.Collections.Generic
Imports System.Linq
' ...

Public Class SynonymDBSchemaProvider
    Inherits DevExpress.DataAccess.Sql.DBSchemaProviderEx
    Public Overrides Function GetTables(connection As SqlDataConnection, ParamArray tableList As String()) As DBTable()
        Dim tables As List(Of DBTable) = MyBase.GetTables(connection, tableList).ToList()
        If connection.Name = "OracleConnection" Then
            tables.Add(New DBTable("Regions") With { _
                Key .Columns = {New DBColumn() With { _
                    Key .Name = "REGION_ID", _
                    Key .ColumnType = DBColumnType.Int32 _
                }, New DBColumn() With { _
                    Key .Name = "REGION_NAME", _
                    Key .ColumnType = DBColumnType.[String], _
                    Key .Size = 25 _
                }} _
            })
        End If

        Return tables.ToArray()
    End Function
End Class

Register the Schema Provider in a WinForms Reporting Application

The following code registers a custom database schema provider in an End-User Report Designer by calling the XRDesignMdiController.AddService method.

C#

using DevExpress.DataAccess.Sql;
using DevExpress.XtraReports.UserDesigner;
// ...

public partial class Form1 : XRDesignRibbonForm {
    public Form1() {
        InitializeComponent();
        DesignMdiController.AddService(typeof(IDBSchemaProviderEx), new SynonymDBSchemaProvider());
    }
}

VB.NET

Imports DevExpress.DataAccess.Sql
Imports DevExpress.XtraReports.UserDesigner
' ...

Public Class Form1
    Inherits XRDesignRibbonForm

    Public Sub New()
        InitializeComponent()
        DesignMdiController.AddService(GetType(IDBSchemaProviderEx), New SynonymDBSchemaProvider())
    End Sub

End Class