| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.drill.exec.planner.sql; |
| |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| import org.apache.calcite.rel.type.RelDataType; |
| import org.apache.calcite.rel.type.RelDataTypeFactory; |
| import org.apache.calcite.rex.RexBuilder; |
| import org.apache.calcite.rex.RexNode; |
| import org.apache.calcite.sql.SqlCall; |
| import org.apache.calcite.sql.SqlIntervalQualifier; |
| import org.apache.calcite.sql.SqlNode; |
| import org.apache.calcite.sql.fun.SqlStdOperatorTable; |
| import org.apache.calcite.sql.type.SqlTypeName; |
| import org.apache.calcite.sql2rel.SqlRexContext; |
| import org.apache.calcite.sql2rel.SqlRexConvertlet; |
| |
| public class DrillExtractConvertlet implements SqlRexConvertlet { |
| |
| public final static DrillExtractConvertlet INSTANCE = new DrillExtractConvertlet(); |
| |
| private DrillExtractConvertlet() { |
| } |
| |
| /* |
| * Custom convertlet to handle extract functions. Optiq rewrites |
| * extract functions as divide and modulo functions, based on the |
| * data type. We cannot do that in Drill since we don't know the data type |
| * till we start scanning. So we don't rewrite extract and treat it as |
| * a regular function. |
| */ |
| @Override |
| public RexNode convertCall(SqlRexContext cx, SqlCall call) { |
| final RexBuilder rexBuilder = cx.getRexBuilder(); |
| final List<SqlNode> operands = call.getOperandList(); |
| final List<RexNode> exprs = new LinkedList<>(); |
| |
| String timeUnit = ((SqlIntervalQualifier) operands.get(0)).timeUnitRange.toString(); |
| |
| RelDataTypeFactory typeFactory = cx.getTypeFactory(); |
| |
| //RelDataType nullableReturnType = |
| |
| for (SqlNode node: operands) { |
| exprs.add(cx.convertExpression(node)); |
| } |
| |
| final RelDataType returnType; |
| if(call.getOperator() == SqlStdOperatorTable.EXTRACT) { |
| // Legacy code: |
| // The return type is wrong! |
| // Legacy code choose SqlTypeName.BIGINT simply to avoid conflicting against Calcite's inference mechanism |
| // (, which chose BIGINT in validation phase already) |
| // Determine NULL-able using 2nd argument's Null-able. |
| returnType = typeFactory.createTypeWithNullability(typeFactory.createSqlType(SqlTypeName.BIGINT), exprs.get(1).getType().isNullable()); |
| } else { |
| // Determine NULL-able using 2nd argument's Null-able. |
| returnType = typeFactory.createTypeWithNullability( |
| typeFactory.createSqlType( |
| TypeInferenceUtils.getSqlTypeNameForTimeUnit(timeUnit)), |
| exprs.get(1).getType().isNullable()); |
| } |
| |
| return rexBuilder.makeCall(returnType, call.getOperator(), exprs); |
| } |
| } |
| |