public virtual ProjectionExpression AddOuterJoinTest(ProjectionExpression proj)
{
Expression test = GetOuterJoinTest(proj.Select);
SelectExpression select = proj.Select;
ColumnExpression testCol = null;
// look to see if test expression exists in columns already
foreach (ColumnDeclaration col in select.Columns)
{
if (test.Equals(col.Expression))
{
QueryType colType = TypeSystem.GetColumnType(test.Type);
testCol = new ColumnExpression(test.Type, colType, select.Alias, col.Name);
break;
}
}
if (testCol == null)
{
// add expression to projection
testCol = test as ColumnExpression;
string colName = (testCol != null) ? testCol.Name : "Test";
colName = proj.Select.Columns.GetAvailableColumnName(colName);
QueryType colType = TypeSystem.GetColumnType(test.Type);
select = select.AddColumn(new ColumnDeclaration(colName, test, colType));
testCol = new ColumnExpression(test.Type, colType, select.Alias, colName);
}
var newProjector = new OuterJoinedExpression(testCol, proj.Projector);
return(new ProjectionExpression(select, newProjector, proj.Aggregator));
}
internal virtual DbProjectionExpression AddOuterJoinTest(DbProjectionExpression proj)
{
var test = this.GetOuterJoinTest(proj.Select);
var select = proj.Select;
var testCol = null as DbColumnExpression;
foreach (var col in select.Columns)
{
if (test.Equals(col.Expression))
{
testCol = new DbColumnExpression(test.Type, TypeSystem.GetColumnType(test.Type), select.Alias, col.Name);
break;
}
}
if (testCol == null)
{
testCol = test as DbColumnExpression;
var colName = testCol != null ? testCol.Name : "Test";
if (colName != null)
{
colName = proj.Select.Columns.GetAvailableColumnName(colName);
}
var colType = this.TypeSystem.GetColumnType(test.Type);
if (colType != null)
{
select = select.AddColumn(new DbColumnDeclaration(colName, test, colType));
testCol = new DbColumnExpression(test.Type, colType, select.Alias, colName);
}
}
return(new DbProjectionExpression
(
select,
new DbOuterJoinedExpression(testCol, proj.Projector),
proj.Aggregator
));
}