a3e588f39c
This commit mainly implements the new materialized view selector which supports SPJ<->SPJG. Two parameters are currently used to regulate this function. 1. test_materialized_view: When this parameter is set to true, the user can create a materialized view for the duplicate table by using 'CREATE MATERIALIZED VIEW' command. At the same time, if the result of the new materialized views is different from the old version during the query, an error will be reported. This parameter is false by default, which means that the new version of the materialized view function cannot be enabled. 2. use_old_mv_selector: When this parameter is set to true, the result of the old version selector will be selected. If set to false, the result of the new version selector will be selected. This parameter is true by default, which means that the old selector is used. If the default values of the above two parameters do not change, there will be no behavior changes in the current version. The main steps for the new selector are as follows: 1. Predicates stage: This stage will mainly filter out all materialized views that do not meet the current query requirements. 2. Priorities stage: This stage will sort the results of the first stage and choose the best materialized view. The predicates phase is divided into 6 steps: 1. Calculate the predicate gap between the current query and view. 2. Whether the columns in the view can meet the needs of the compensating predicates. 3. Determine whether the group by columns of view match the group by columns of query. 4. Determine whether the aggregate columns of view match the aggregate columns of query. 5. Determine whether the output columns of view match the output columns of query. 6. Add partial materialized views The priorities phase is divided into two steps: 1. Find the materialized view that matches the best prefix index 2. Find the materialized view with the least amount of data The biggest difference between the current materialized view selector and the previous one is that it supports SPJ <-> SPJG.
Apache Doris (incubating)
Doris is an MPP-based interactive SQL data warehousing for reporting and analysis. Its original name was Palo, developed in Baidu. After donating it to Apache Software Foundation, it was renamed Doris.
1. License
2. Technology
Doris mainly integrates the technology of Google Mesa and Apache Impala, and it is based on a column-oriented storage engine and can communicate by MySQL client.
3. User cases
Doris not only provides high concurrent low latency point query performance, but also provides high throughput queries of ad-hoc analysis.
Doris not only provides batch data loading, but also provides near real-time mini-batch data loading.
Doris also provides high availability, reliability, fault tolerance, and scalability.
The simplicity (of developing, deploying and using) and meeting many data serving requirements in single system are the main features of Doris (refer to Overview).
4. Compile and install
Currently only supports Docker environment and Linux OS, such as Ubuntu and CentOS.
4.1 Compile in Docker environment (Recommended)
We offer a docker image as a Doris compilation environment. You can compile Doris from source in it and run the output binaries in other Linux environment.
Firstly, you must be install and start docker service.
And then you could build Doris as following steps:
Step1: Pull the docker image with Doris building environment
$ docker pull apachedoris/doris-dev:build-env-1.2
You can check it by listing images, for example:
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
apachedoris/doris-dev build-env-1.2 69cf7fff9d10 2 weeks ago 4.12GB
NOTE: You may have to use different images to compile from source.
image version commit id release version apachedoris/doris-dev:build-env before ff0dd0d 0.8.x, 0.9.x apachedoris/doris-dev:build-env-1.1 ff0dd0d or later 0.10.x or 0.11.x apachedoris/doris-dev:build-env-1.2 1648226 or later 0.12.x or later
Step2: Run the Docker image
You can run the image directly:
$ docker run -it apachedoris/doris-dev:build-env-1.2
Or if you want to compile the source located in your local host, you can map the local directory to the image by running:
$ docker run -it -v /your/local/path/incubator-doris-DORIS-x.x.x-release/:/root/incubator-doris-DORIS-x.x.x-release/ apachedoris/doris-dev:build-env-1.2
Step3: Download Doris source
Now you should attached in docker environment.
You can download Doris source by release package or by git clone in image.
(If you already downloaded the source in your local host and map it to the image in Step2, you can skip this step.)
$ wget https://dist.apache.org/repos/dist/dev/incubator/doris/xxx.tar.gz
or
$ git clone https://github.com/apache/incubator-doris.git
Step4: Build Doris
Enter Doris source path and build Doris.
$ sh build.sh
After successfully building, it will install binary files in the directory output/.
4.2 For Linux OS
Prerequisites
You must be install following softwares:
GCC 5.3.1+, Oracle JDK 1.8+, Python 2.7+, Apache Maven 3.5+, CMake 3.4.3+
After you installed above all, you also must be set them to environment variable PATH and set JAVA_HOME.
If your GCC version is lower than 5.3.1, you can run:
sudo yum install devtoolset-4-toolchain -y
and then, set the path of GCC (e.g /opt/rh/devtoolset-4/root/usr/bin) to the environment variable PATH.
Compile and install
Run the following script, it will compile thirdparty libraries and build whole Doris.
sh build.sh
After successfully building, it will install binary files in the directory output/.
5. License Notice
Some of the third-party dependencies' license are not compatible with Apache 2.0 License. So you may have to disable
some features of Doris to be complied with Apache 2.0 License. Details can be found in thirdparty/LICENSE.txt
6. Reporting Issues
If you find any bugs, please file a GitHub issue.
7. Links
- Doris official site - http://doris.incubator.apache.org
- User Manual (GitHub Wiki) - https://github.com/apache/incubator-doris/wiki
- Developer Mailing list - Subscribe to dev@doris.incubator.apache.org to discuss with us.
- Gitter channel - https://gitter.im/apache-doris/Lobby - Online chat room with Doris developers.
- Overview - https://github.com/apache/incubator-doris/wiki/Doris-Overview
- Compile and install - https://github.com/apache/incubator-doris/wiki/Doris-Install
- Getting start - https://github.com/apache/incubator-doris/wiki/Getting-start
- Deploy and Upgrade - https://github.com/apache/incubator-doris/wiki/Doris-Deploy-%26-Upgrade
- User Manual - https://github.com/apache/incubator-doris/wiki/Doris-Create%2C-Load-and-Delete
- FAQs - https://github.com/apache/incubator-doris/wiki/Doris-FAQ