com.hazelcast.org.apache.calcite.sql.fun.SqlFirstLastValueAggFunction 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 com.hazelcast.org.apache.calcite.sql.fun;
import com.hazelcast.org.apache.calcite.rel.type.RelDataType;
import com.hazelcast.org.apache.calcite.rel.type.RelDataTypeFactory;
import com.hazelcast.org.apache.calcite.sql.SqlAggFunction;
import com.hazelcast.org.apache.calcite.sql.SqlFunctionCategory;
import com.hazelcast.org.apache.calcite.sql.SqlKind;
import com.hazelcast.org.apache.calcite.sql.type.OperandTypes;
import com.hazelcast.org.apache.calcite.sql.type.ReturnTypes;
import com.hazelcast.org.apache.calcite.sql.type.SqlTypeName;
import com.hazelcast.org.apache.calcite.util.Optionality;
import com.hazelcast.com.google.common.base.Preconditions;
import com.hazelcast.com.google.common.collect.ImmutableList;
import java.util.List;
/**
* FIRST_VALUE
and LAST_VALUE
aggregate functions
* return the first or the last value in a list of values that are input to the
* function.
*/
public class SqlFirstLastValueAggFunction extends SqlAggFunction {
//~ Constructors -----------------------------------------------------------
public SqlFirstLastValueAggFunction(SqlKind kind) {
super(
kind.name(),
null,
kind,
ReturnTypes.ARG0_NULLABLE_IF_EMPTY,
null,
OperandTypes.ANY,
SqlFunctionCategory.NUMERIC,
false,
true,
Optionality.FORBIDDEN);
Preconditions.checkArgument(kind == SqlKind.FIRST_VALUE
|| kind == SqlKind.LAST_VALUE);
}
@Deprecated // to be removed before 2.0
public SqlFirstLastValueAggFunction(boolean firstFlag) {
this(firstFlag ? SqlKind.FIRST_VALUE : SqlKind.LAST_VALUE);
}
//~ Methods ----------------------------------------------------------------
@SuppressWarnings("deprecation")
@Override public List getParameterTypes(RelDataTypeFactory typeFactory) {
return ImmutableList.of(
typeFactory.createTypeWithNullability(
typeFactory.createSqlType(SqlTypeName.ANY), true));
}
@SuppressWarnings("deprecation")
@Override public RelDataType getReturnType(RelDataTypeFactory typeFactory) {
return typeFactory.createTypeWithNullability(
typeFactory.createSqlType(SqlTypeName.ANY), true);
}
@Override public boolean allowsNullTreatment() {
return true;
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy