Bug 153387 Database item can't be dragged and dropped onto editor field
Steps to reproduce: 1.Start up BIRT in Mac OS X; 2.File->New->Project; 3.File->New->Report Design; 4.In Data Explorer, create a New Data Source, and choose "Classic Models Inc. Sample DataBase", press "Next" and then press "finish"; 5.In Data Explorer, create a New Data Set, press "Next"; 6.In the popup window, expand the "CLASSICMODELS", select and drag a item onto the editor field at right side.
data/org.eclipse.birt.report.data.oda.jdbc.ui/src/org/eclipse/birt/report/data/oda/jdbc/ui/editors/SQLDataSetEditorPage.java
{
			Image image = tableImage;
		
			if ( tablesRs != null )
			{
				int numberOfTable;
				
				Preferences preferences = JdbcPlugin.getDefault( ).getPluginPreferences( );
				if ( preferences.contains( DateSetPreferencePage.USER_MAX_NUM_OF_TABLE_EACH_SCHEMA ) )
				{
					numberOfTable = preferences.getInt( DateSetPreferencePage.USER_MAX_NUM_OF_TABLE_EACH_SCHEMA );
				}
				else
				{
					numberOfTable = DateSetPreferencePage.DEFAULT_MAX_NUM_OF_TABLE_EACH_SCHEMA;
					preferences.setValue( DateSetPreferencePage.USER_MAX_NUM_OF_TABLE_EACH_SCHEMA,
							numberOfTable );
				}
				int count = 0;
				while ( tablesRs.next( ) && count < numberOfTable )
				{
					String tableName = tablesRs.getString( "TABLE_NAME" );
					String type = tablesRs.getString( "TABLE_TYPE" );
					if ( type.equalsIgnoreCase( "SYSTEM TABLE" ) )
						continue;
					
					
					int dbType = DbObject.TABLE_TYPE;
					if ( type.equalsIgnoreCase( "TABLE" ) )
					{