korlov42 commented on a change in pull request #216: URL: https://github.com/apache/ignite-3/pull/216#discussion_r689451066
########## File path: modules/schema/src/main/java/org/apache/ignite/internal/schema/row/TemporalTypesHelper.java ########## @@ -0,0 +1,296 @@ +/* + * 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.ignite.internal.schema.row; + +import java.time.LocalDate; +import java.time.LocalTime; +import org.apache.ignite.internal.schema.TemporalNativeType; + +/** + * Helper class for temporal type conversions. + * <p> + * Provides methods to encode/decode temporal types in a compact way for futher writing to row. + * Conversion preserves natural type order. + * <p> + * DATE is a fixed-length type which compacted representation keeps ordering, value is signed and fit into a 3-bytes. + * Thus, DATE value can be compared by bytes where first byte is signed and others - unsigned. + * Thus temporal functions, like YEAR(), can easily extracts fields with a mask, + * <p> + * Date compact structure: + * ┌──────────────┬─────────┬────────┐ + * │ Year(signed) │ Month │ Day │ + * ├──────────────┼─────────┼────────┤ + * │ 15 bits │ 4 bits │ 5 bits │ + * └──────────────┴─────────┴────────┘ + * <p> + * TIME is a fixed-length type supporting accuracy from 1 second up to 1 nanosecond. + * Compacted time representation keeps ordering, values fits to 4-6 bytes value. + * The first 18 bits is used for hour, munutes and seconds, and the last bits for fractional seconds: Review comment: ```suggestion * The first 18 bits is used for hours, minutes and seconds, and the last bits for fractional seconds: ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
