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IRWDataObject's code to select records from relational tables/entities between
Student & Class
This code show you how easy to build a data-view with your .net language.
string sqlConnectionString = "...";
// define view-schema with Student class as first entity
ViewSchema vs = new ViewSchema(typeof(Student), null);
// define relation to Class with foreign-primary key columns
vs.Add(typeof(Student), SqlRelational.InnerJoin,
typeof(Class), typeof(Student), "ClassID",
SqlComparison.Equal, typeof(Class), "ID", null);
// select a record with criteria Name
// define where-schema for fields Name with default value is 'Andy'
WhereSchema ws = new WhereSchema(vs);
ws.Add(SqlConditional.And, typeof(Student), typeof(Student),
"Name", SqlComparison.Equal, "Andy");
// define mapper object
SelectMapper m = new SelectMapper(sqlConnectionString, vs);
// execute view-schema with new Student-object
// return value is ViewResult object
ViewResult result = m.Execute(null);
// display record from ViewResult object
foreach (ViewResultRecordInfo item in result)
{
for (int i = 0; i < vs.Columns.Length; i++)
{
Console.Write(item[vs.Columns[i].TableColumnName,
vs.Columns[i].TableEntity].Value.ToString().PadLeft(25));
}
Console.WriteLine("\n");
}
Note : You can even define realtion to a view-schema
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