org.apache.calcite.sql.fun.SqlItemOperator 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.sql.fun;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rel.type.RelDataTypeFactory;
import org.apache.calcite.rel.type.RelDataTypeField;
import org.apache.calcite.sql.SqlCall;
import org.apache.calcite.sql.SqlCallBinding;
import org.apache.calcite.sql.SqlKind;
import org.apache.calcite.sql.SqlNode;
import org.apache.calcite.sql.SqlOperandCountRange;
import org.apache.calcite.sql.SqlOperatorBinding;
import org.apache.calcite.sql.SqlSpecialOperator;
import org.apache.calcite.sql.SqlWriter;
import org.apache.calcite.sql.parser.SqlParserPos;
import org.apache.calcite.sql.type.OperandTypes;
import org.apache.calcite.sql.type.SqlOperandCountRanges;
import org.apache.calcite.sql.type.SqlSingleOperandTypeChecker;
import org.apache.calcite.sql.type.SqlTypeFamily;
import org.apache.calcite.sql.type.SqlTypeName;
import java.util.Arrays;
/**
* The item operator {@code [ ... ]}, used to access a given element of an array or map. For
* example, {@code myArray[3]} or {@code "myMap['foo']"}.
*
* This class was copied over from Calcite to fix the infer type for ROW. If the ROW is nullable
* force the accessed field to be nullable as well. Additionally in the checker we verify the
* argument is a literal in case of a ROW.
*/
class SqlItemOperator extends SqlSpecialOperator {
private static final SqlSingleOperandTypeChecker ARRAY_OR_MAP =
OperandTypes.or(
OperandTypes.family(SqlTypeFamily.ARRAY),
OperandTypes.family(SqlTypeFamily.MAP),
OperandTypes.family(SqlTypeFamily.ANY));
SqlItemOperator() {
super("ITEM", SqlKind.ITEM, 100, true, null, null, null);
}
@Override
public ReduceResult reduceExpr(int ordinal, TokenSequence list) {
SqlNode left = list.node(ordinal - 1);
SqlNode right = list.node(ordinal + 1);
return new ReduceResult(
ordinal - 1,
ordinal + 2,
createCall(
SqlParserPos.sum(
Arrays.asList(
left.getParserPosition(),
right.getParserPosition(),
list.pos(ordinal))),
left,
right));
}
@Override
public void unparse(SqlWriter writer, SqlCall call, int leftPrec, int rightPrec) {
call.operand(0).unparse(writer, leftPrec, 0);
final SqlWriter.Frame frame = writer.startList("[", "]");
call.operand(1).unparse(writer, 0, 0);
writer.endList(frame);
}
@Override
public SqlOperandCountRange getOperandCountRange() {
return SqlOperandCountRanges.of(2);
}
@Override
public boolean checkOperandTypes(SqlCallBinding callBinding, boolean throwOnFailure) {
final SqlNode left = callBinding.operand(0);
final SqlNode right = callBinding.operand(1);
if (!ARRAY_OR_MAP.checkSingleOperandType(callBinding, left, 0, throwOnFailure)) {
return false;
}
final SqlSingleOperandTypeChecker checker = getChecker(callBinding);
return checker.checkSingleOperandType(callBinding, right, 0, throwOnFailure);
}
private SqlSingleOperandTypeChecker getChecker(SqlCallBinding callBinding) {
final RelDataType operandType = callBinding.getOperandType(0);
switch (operandType.getSqlTypeName()) {
case ARRAY:
return OperandTypes.family(SqlTypeFamily.INTEGER);
case MAP:
return OperandTypes.family(operandType.getKeyType().getSqlTypeName().getFamily());
case ROW:
return OperandTypes.and(OperandTypes.LITERAL, OperandTypes.CHARACTER);
case ANY:
case DYNAMIC_STAR:
return OperandTypes.or(
OperandTypes.family(SqlTypeFamily.INTEGER),
OperandTypes.family(SqlTypeFamily.CHARACTER));
default:
throw callBinding.newValidationSignatureError();
}
}
@Override
public String getAllowedSignatures(String name) {
return "[]\n" + "