org.apache.calcite.adapter.druid.DruidSqlOperatorConverter Maven / Gradle / Ivy
/*
* 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.calcite.adapter.druid;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.sql.SqlOperator;
import javax.annotation.Nullable;
/**
* Defines how to convert RexNode with a given calcite SQL operator to Druid expressions
*/
public interface DruidSqlOperatorConverter {
/**
* Returns the calcite SQL operator corresponding to Druid operator.
*
* @return operator
*/
SqlOperator calciteOperator();
/**
* Translate rexNode to valid Druid expression.
* @param rexNode rexNode to translate to Druid expression
* @param rowType row type associated with rexNode
* @param druidQuery druid query used to figure out configs/fields related like timeZone
*
* @return valid Druid expression or null if it can not convert the rexNode
*/
@Nullable String toDruidExpression(RexNode rexNode, RelDataType rowType, DruidQuery druidQuery);
}
// End DruidSqlOperatorConverter.java