public void Query_ExecuteScalarReturnsNullIfEmpty()
{
var dataTable = TestData.IdNameTable();
var dataContext = DataContext.Default.AddTables(dataTable);
var query = Query.Create(dataContext, "SELECT * FROM Table WHERE FALSE");
var result = query.ExecuteScalar();
Assert.Equal(null, result);
}
public void Query_ExecuteScalarReturnsFirstValue()
{
var dataTable = TestData.IdNameTable();
var dataContext = DataContext.Default.AddTables(dataTable);
var query = Query.Create(dataContext, "SELECT * FROM Table");
var result = query.ExecuteScalar();
var expected = dataTable.Rows[0][0];
Assert.Equal(expected, result);
}
public void Query_ExecuteScalarOfTThrows_IfTypeDoesNotMatch()
{
var dataTable = TestData.IdNameTable();
var dataContext = DataContext.Default.AddTables(dataTable);
var query = Query.Create(dataContext, "SELECT * FROM Table");
Assert.Throws <InvalidCastException>(() =>
{
query.ExecuteScalar <string>();
});
}
public static Compilation WithIdNameTable(this Compilation compilation)
{
var table = TestData.IdNameTable();
return(compilation.WithDataContext(DataContext.Default.AddTables(table)));
}