dfbeeccd47
This pull request includes some implementations of the statistics(https://github.com/apache/incubator-doris/issues/6370), it will not affect any existing code and users will not be able to create statistics job. After receiving the statistics collection statement, it generates a job. Here it implements the division of statistics collection jobs according to the following statistics categories: table: - `row_count`: table row count are critical in estimating cardinality and memory usage of scan nodes. - `data_size`: table size, not applicable to CBO, mainly used to monitor and manage table size. column: - `num_distinct_value`: used to determine the selectivity of an equivalent expression. - `min`: The minimum value. - `max`: The maximum value. - `num_nulls`: number of nulls. - `avg_col_len`: the average length of a column, in bytes, is used for memory and network IO evaluation. - `max_col_len`: the Max length of the column, in bytes, is used for memory and network IO evaluation. After the job is divided, statistics tasks will be obtained.
# 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. # fe-common This module is used to store some common classes of other modules. # spark-dpp This module is Spark DPP program, used for Spark Load function. Depends: fe-common # fe-core This module is the main process module of FE. Depends: fe-common, spark-dpp