FunctionVolatility.java

// 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.doris.catalog;

import java.util.Locale;

/** Function volatility controls which optimizer rewrites are safe for a function call. */
public enum FunctionVolatility {
    IMMUTABLE,
    STABLE,
    VOLATILE;

    public static FunctionVolatility fromString(String value) {
        if (value == null) {
            return IMMUTABLE;
        }
        try {
            return FunctionVolatility.valueOf(value.trim().toUpperCase(Locale.ROOT));
        } catch (IllegalArgumentException e) {
            throw new IllegalArgumentException("Invalid volatility: '" + value
                    + "'. Expected one of: immutable, stable, volatile", e);
        }
    }

    public String toSql() {
        return name().toLowerCase(Locale.ROOT);
    }
}