SqlFunction
public class SqlFunction : ISqlExpression, IQueryElement, IEquatable<ISqlExpression>, ISqlExpressionWalkable
public SqlFunction(Type systemType, string name, bool isAggregate, bool isPure, ISqlExpression[] parameters)
public SqlFunction(Type systemType, string name, bool isAggregate, int precedence, ISqlExpression[] parameters)
public SqlFunction(Type systemType, string name, bool isAggregate, bool isPure, int precedence, ISqlExpression[] parameters)