Deveel.Data.Sql.Query.ConstantSelectNode Class Reference

The node for evaluating an expression that contains entirely constant values (no variables). More...

Inheritance diagram for Deveel.Data.Sql.Query.ConstantSelectNode:

Public Member Functions
	ConstantSelectNode (IQueryPlanNode child, SqlExpression expression)
override ITable	Evaluate (IRequest context)

Protected Member Functions
override void	GetData (SerializeData data)
Protected Member Functions inherited from Deveel.Data.Sql.Query.SingleQueryPlanNode
	SingleQueryPlanNode (IQueryPlanNode child)
	SingleQueryPlanNode (ObjectData data)

Properties
SqlExpression	Expression [get, private set]
Properties inherited from Deveel.Data.Sql.Query.SingleQueryPlanNode
IQueryPlanNode	Child [get, private set]
	Gets the single child node of the plan. More...

Private Member Functions
	ConstantSelectNode (ObjectData data)

Detailed Description

The node for evaluating an expression that contains entirely constant values (no variables).

Definition at line 30 of file ConstantSelectNode.cs.

Constructor & Destructor Documentation

Deveel.Data.Sql.Query.ConstantSelectNode.ConstantSelectNode ( IQueryPlanNode  child, SqlExpression  expression  )

inline

Definition at line 31 of file ConstantSelectNode.cs.

            : base(child) {
            Expression = expression;
        }

Deveel.Data.Sql.Query.ConstantSelectNode.ConstantSelectNode ( ObjectData  data )

inlineprivate

Definition at line 36 of file ConstantSelectNode.cs.

            : base(data) {
            Expression = data.GetValue<SqlExpression>("Expression");
        }

Member Function Documentation

override ITable Deveel.Data.Sql.Query.ConstantSelectNode.Evaluate ( IRequest  context )

inlinevirtual

Implements Deveel.Data.Sql.Query.SingleQueryPlanNode.

Definition at line 44 of file ConstantSelectNode.cs.

                                                          {
            // Evaluate the expression
            var exp = Expression.Evaluate(context, null);
            if (exp.ExpressionType != SqlExpressionType.Constant)
                throw new InvalidOperationException();

            var v = ((SqlConstantExpression) exp).Value;

            // If it evaluates to NULL or FALSE then return an empty set
            if (v.IsNull || v == false)
                return Child.Evaluate(context).EmptySelect();

            return Child.Evaluate(context);
        }

override void Deveel.Data.Sql.Query.ConstantSelectNode.GetData ( SerializeData  data )

inlineprotectedvirtual

Reimplemented from Deveel.Data.Sql.Query.SingleQueryPlanNode.

Definition at line 59 of file ConstantSelectNode.cs.

                                                            {
            data.SetValue("Expression", Expression);
        }

Property Documentation

SqlExpression Deveel.Data.Sql.Query.ConstantSelectNode.Expression

getprivate set

Definition at line 41 of file ConstantSelectNode.cs.

---

The documentation for this class was generated from the following file:

• /var/calculate/remote/distfiles/egit-src/deveeldb.git/src/deveeldb/Deveel.Data.Sql.Query/ConstantSelectNode.cs