Azavea.Open.DAO.PostgreSQL.PostgreSqlDaLayer.ExpressionToQuery C# (CSharp) Method

        protected override bool ExpressionToQuery(SqlDaQuery queryToAddTo, IExpression expr,
            ClassMapping mapping, string colPrefix, string booleanOperator)
        {
            // All the spatial expressions we support modify the sql.
            bool retVal = true;
            bool trueOrNot = expr.TrueOrNot();
            if (expr is IntersectsExpression)
            {
                queryToAddTo.Sql.Append(booleanOperator);
                IntersectsExpression intersects = (IntersectsExpression)expr;
                queryToAddTo.Sql.Append("ST_Intersects(ST_GeomFromEWKT(?),");
                queryToAddTo.Params.Add(_ewktWriter.Write(intersects.Shape));
                queryToAddTo.Sql.Append(colPrefix).Append(mapping.AllDataColsByObjAttrs[intersects.Property]);
                queryToAddTo.Sql.Append(")");
            }
            else if (expr is WithinExpression)
            {
                queryToAddTo.Sql.Append(booleanOperator);
                WithinExpression within = (WithinExpression)expr;
                queryToAddTo.Sql.Append("ST_Contains(ST_GeomFromEWKT(?),");
                queryToAddTo.Params.Add(_ewktWriter.Write(within.Shape));
                queryToAddTo.Sql.Append(colPrefix).Append(mapping.AllDataColsByObjAttrs[within.Property]);
                queryToAddTo.Sql.Append(")");
            }
            else if (expr is ContainsExpression)
            {
                queryToAddTo.Sql.Append(booleanOperator);
                ContainsExpression contains = (ContainsExpression)expr;
                queryToAddTo.Sql.Append("ST_Contains(");
                queryToAddTo.Sql.Append(colPrefix).Append(mapping.AllDataColsByObjAttrs[contains.Property]);
                queryToAddTo.Sql.Append(",ST_GeomFromEWKT(?)");
                queryToAddTo.Params.Add(_ewktWriter.Write(contains.Shape));
                queryToAddTo.Sql.Append(")");
            }
            else if (expr is AbstractDistanceExpression)
            {
                queryToAddTo.Sql.Append(booleanOperator);
                AbstractDistanceExpression dist = (AbstractDistanceExpression)expr;

                queryToAddTo.Sql.Append("ST_Distance(");
                queryToAddTo.Sql.Append(colPrefix).Append(mapping.AllDataColsByObjAttrs[dist.Property]);
                queryToAddTo.Sql.Append(", ST_GeomFromEWKT(?))");
                queryToAddTo.Params.Add(EWKTWriter.ToPoint((IPoint)dist.Shape));
                if (dist is LesserDistanceExpression)
                {
                    queryToAddTo.Sql.Append(trueOrNot ? " < ?" : " >= ?");
                }
                else if (expr is GreaterDistanceExpression)
                {
                    queryToAddTo.Sql.Append(trueOrNot ? " > ?" : " <= ?");
                }
                else
                {
                    throw new ArgumentException("Distance expression type " +
                                                expr.GetType() + " not supported.", "expr");
                }
                queryToAddTo.Params.Add(dist.Distance);
            }
            else if (expr is AbstractDistanceSphereExpression)
            {
                queryToAddTo.Sql.Append(booleanOperator);
                AbstractDistanceSphereExpression dist = (AbstractDistanceSphereExpression)expr;
                if (!(dist.Shape is IPoint))
                {
                    throw new ArgumentException("Spherical distance from a non-point is not supported.");
                }

                queryToAddTo.Sql.Append("ST_distance_sphere(");
                queryToAddTo.Sql.Append(colPrefix).Append(mapping.AllDataColsByObjAttrs[dist.Property]);
                queryToAddTo.Sql.Append(", ST_GeomFromEWKT(?))");
                queryToAddTo.Params.Add(EWKTWriter.ToPoint((IPoint)dist.Shape));
                if (dist is LesserDistanceSphereExpression)
                {
                    queryToAddTo.Sql.Append(trueOrNot ? " < ?" : " >= ?");
                }
                else if (expr is GreaterDistanceSphereExpression)
                {
                    queryToAddTo.Sql.Append(trueOrNot ? " > ?" : " <= ?");
                }
                else
                {
                    throw new ArgumentException("Distance expression type " +
                                                expr.GetType() + " not supported.", "expr");
                }
                queryToAddTo.Params.Add(dist.Distance);
            }
            else
            {
                // Fall back to the stuff supported by the base class.
                retVal = base.ExpressionToQuery(queryToAddTo, expr, mapping, colPrefix, booleanOperator);
            }
            return retVal;
        }