/*
 * 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.hadoop.hive.ql.optimizer.calcite.reloperators;

import org.apache.calcite.sql.SqlFunction;
import org.apache.calcite.sql.SqlFunctionCategory;
import org.apache.calcite.sql.SqlKind;
import org.apache.calcite.sql.type.OperandTypes;
import org.apache.calcite.sql.type.ReturnTypes;

/**
 * Sql UNIX_TIMESTAMP calcite operator.
 */
public class HiveToUnixTimestampSqlOperator {
  public static final SqlFunction INSTANCE =
      new SqlFunction("UNIX_TIMESTAMP", SqlKind.OTHER_FUNCTION, ReturnTypes.BIGINT, null,
          OperandTypes.or(OperandTypes.NILADIC,
              OperandTypes.or(OperandTypes.STRING, OperandTypes.TIMESTAMP, OperandTypes.DATE),
              OperandTypes.STRING_STRING), SqlFunctionCategory.NUMERIC) {
        @Override
        public boolean isDynamicFunction() {
          return true;
        }
      };
}
