protected virtual Expression VisitOuterJoined(OuterJoinedExpression outer)
{
var test = this.Visit(outer.Test);
var expression = this.Visit(outer.Expression);
return(this.UpdateOuterJoined(outer, test, expression));
}
protected OuterJoinedExpression UpdateOuterJoined(OuterJoinedExpression outer, Expression test, Expression expression)
{
if (test != outer.Test || expression != outer.Expression)
{
return(new OuterJoinedExpression(test, expression));
}
return(outer);
}
protected virtual Expression VisitOuterJoined(OuterJoinedExpression outer)
{
this.Write("Outer(");
this.WriteLine(Indentation.Inner);
this.Visit(outer.Test);
this.Write(", ");
this.WriteLine(Indentation.Same);
this.Visit(outer.Expression);
this.WriteLine(Indentation.Outer);
this.Write(")");
return(outer);
}
public static ProjectionExpression AddOuterJoinTest(this ProjectionExpression proj, Dialect.Dialect language, Expression expression)
{
string colName = proj.Select.Columns.GetAvailableColumnName("Test");
var colType = SqlType.Get(expression.Type);
SelectExpression newSource = proj.Select.AddColumn(new ColumnDeclaration(colName, expression, colType));
Expression newProjector =
new OuterJoinedExpression(
new ColumnExpression(expression.Type, colType, newSource.Alias, colName),
proj.Projector
);
return(new ProjectionExpression(newSource, newProjector, proj.Aggregator));
}