Add MariaDB connector

.github/workflows/ci.yml

@@ -324,6 +324,7 @@ jobs:
             !:trino-mysql,
             !:trino-postgresql,
             !:trino-sqlserver,
+            !:trino-mariadb,
             !:trino-oracle,
             !:trino-kudu,
             !:trino-druid,
@@ -402,6 +403,7 @@ jobs:
             - { modules: plugin/trino-postgresql }
             - { modules: plugin/trino-sqlserver }
             - { modules: plugin/trino-singlestore }
+            - { modules: plugin/trino-mariadb }
             - { modules: plugin/trino-oracle }
             - { modules: plugin/trino-kudu }
             - { modules: plugin/trino-druid }

core/trino-server/src/main/provisio/trino.xml

@@ -128,6 +128,12 @@
         </artifact>
     </artifactSet>
 
+    <artifactSet to="plugin/mariadb">
+        <artifact id="${project.groupId}:trino-mariadb:zip:${project.version}">
+            <unpack />
+        </artifact>
+    </artifactSet>
+
     <artifactSet to="plugin/mysql">
         <artifact id="${project.groupId}:trino-mysql:zip:${project.version}">
             <unpack />

docs/src/main/sphinx/connector.rst

@@ -25,6 +25,7 @@ from different data sources.
     Kinesis         <connector/kinesis>
     Kudu            <connector/kudu>
     Local File      <connector/localfile>
+    MariaDB         <connector/mariadb>
     Memory          <connector/memory>
     MongoDB         <connector/mongodb>
     MySQL           <connector/mysql>

docs/src/main/sphinx/connector/mariadb.rst

@@ -0,0 +1,162 @@
+=================
+MariaDB connector
+=================
+
+The MariaDB connector allows querying and
+creating tables in an external MariaDB database.
+
+Requirements
+------------
+
+To connect to MariaDB, you need:
+
+* MariaDB version 10.2 or higher.
+* Network access from the Trino coordinator and workers to MariaDB. Port
+  3306 is the default port.
+
+Configuration
+-------------
+
+To configure the MariaDB connector, create a catalog properties file
+in ``etc/catalog`` named, for example, ``mariadb.properties``, to
+mount the MariaDB connector as the ``mariadb`` catalog.
+Create the file with the following contents, replacing the
+connection properties as appropriate for your setup:
+
+.. code-block:: text
+
+    connector.name=mariadb
+    connection-url=jdbc:mariadb://example.net:3306
+    connection-user=root
+    connection-password=secret
+
+.. include:: jdbc-common-configurations.fragment
+
+.. include:: jdbc-case-insensitive-matching.fragment
+
+.. include:: non-transactional-insert.fragment
+
+Querying MariaDB
+----------------
+
+The MariaDB connector provides a schema for every MariaDB *database*.
+You can see the available MariaDB databases by running ``SHOW SCHEMAS``::
+
+    SHOW SCHEMAS FROM mariadb;
+
+If you have a MariaDB database named ``web``, you can view the tables
+in this database by running ``SHOW TABLES``::
+
+    SHOW TABLES FROM mariadb.web;
+
+You can see a list of the columns in the ``clicks`` table in the ``web``
+database using either of the following::
+
+    DESCRIBE mariadb.web.clicks;
+    SHOW COLUMNS FROM mariadb.web.clicks;
+
+Finally, you can access the ``clicks`` table in the ``web`` database::
+
+    SELECT * FROM mariadb.web.clicks;
+
+If you used a different name for your catalog properties file, use
+that catalog name instead of ``mariadb`` in the above examples.
+
+.. mariadb-type-mapping:
+
+Type mapping
+------------
+
+Trino supports the following MariaDB data types:
+
+==================================  ===============================
+MariaDB Type                        Trino Type
+==================================  ===============================
+``boolean``                         ``tinyint``
+``tinyint``                         ``tinyint``
+``smallint``                        ``smallint``
+``int``                             ``integer``
+``bigint``                          ``bigint``
+``tinyint unsigned``                ``smallint``
+``smallint unsigned``               ``integer``
+``mediumint unsigned``              ``integer``
+``integer unsigned``                ``bigint``
+``bigint unsigned``                 ``decimal(20,0)``
+``float``                           ``real``
+``double``                          ``double``
+``decimal(p,s)``                    ``decimal(p,s)``
+``char(n)``                         ``char(n)``
+``tinytext``                        ``varchar(255)``
+``text``                            ``varchar(65535)``
+``mediumtext``                      ``varchar(16777215)``
+``longtext``                        ``varchar``
+``varchar(n)``                      ``varchar(n)``
+``tinyblob``                        ``varbinary``
+``blob``                            ``varbinary``
+``mediumblob``                      ``varbinary``
+``longblob``                        ``varbinary``
+``varbinary(n)``                    ``varbinary``
+``date``                            ``date``
+``time(n)``                         ``time(n)``
+==================================  ===============================
+
+Complete list of `MariaDB data types
+<https://mariadb.com/kb/en/data-types/>`_.
+
+
+.. include:: jdbc-type-mapping.fragment
+
+.. _mariadb-sql-support:
+
+SQL support
+-----------
+
+The connector provides read access and write access to data and metadata in
+a MariaDB database.  In addition to the :ref:`globally available
+<sql-globally-available>` and :ref:`read operation <sql-read-operations>`
+statements, the connector supports the following features:
+
+* :doc:`/sql/insert`
+* :doc:`/sql/delete`
+* :doc:`/sql/truncate`
+* :doc:`/sql/create-table`
+* :doc:`/sql/create-table-as`
+* :doc:`/sql/drop-table`
+* :doc:`/sql/alter-table`
+* :doc:`/sql/create-schema`
+* :doc:`/sql/drop-schema`
+
+.. include:: sql-delete-limitation.fragment
+
+Performance
+-----------
+
+The connector includes a number of performance improvements, detailed in the
+following sections.
+
+.. _mariadb-pushdown:
+
+Pushdown
+^^^^^^^^
+
+The connector supports pushdown for a number of operations:
+
+* :ref:`join-pushdown`
+* :ref:`limit-pushdown`
+* :ref:`topn-pushdown`
+
+:ref:`Aggregate pushdown <aggregation-pushdown>` for the following functions:
+
+* :func:`avg`
+* :func:`count`
+* :func:`max`
+* :func:`min`
+* :func:`sum`
+* :func:`stddev`
+* :func:`stddev_pop`
+* :func:`stddev_samp`
+* :func:`variance`
+* :func:`var_pop`
+* :func:`var_samp`
+
+.. include:: no-pushdown-text-type.fragment

plugin/trino-mariadb/pom.xml

@@ -0,0 +1,164 @@
+<?xml version="1.0"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>io.trino</groupId>
+        <artifactId>trino-root</artifactId>
+        <version>379-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
+    <artifactId>trino-mariadb</artifactId>
+    <description>Trino - MariaDB Connector</description>
+    <packaging>trino-plugin</packaging>
+
+    <properties>
+        <air.main.basedir>${project.parent.basedir}</air.main.basedir>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-base-jdbc</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-plugin-toolkit</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>com.google.inject</groupId>
+            <artifactId>guice</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>javax.inject</groupId>
+            <artifactId>javax.inject</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.mariadb.jdbc</groupId>
+            <artifactId>mariadb-java-client</artifactId>
+        </dependency>
+
+        <!-- used by tests but also needed transitively -->
+        <dependency>
+            <groupId>io.airlift</groupId>
+            <artifactId>log</artifactId>
+            <scope>runtime</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.airlift</groupId>
+            <artifactId>log-manager</artifactId>
+            <scope>runtime</scope>
+        </dependency>
+
+        <!-- Trino SPI -->
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-spi</artifactId>
+            <scope>provided</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.airlift</groupId>
+            <artifactId>slice</artifactId>
+            <scope>provided</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-annotations</artifactId>
+            <scope>provided</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.openjdk.jol</groupId>
+            <artifactId>jol-core</artifactId>
+            <scope>provided</scope>
+        </dependency>
+
+        <!-- for testing -->
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-base-jdbc</artifactId>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-main</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-main</artifactId>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-testing</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.trino</groupId>
+            <artifactId>trino-tpch</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.trino.tpch</groupId>
+            <artifactId>tpch</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.airlift</groupId>
+            <artifactId>testing</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.jetbrains</groupId>
+            <artifactId>annotations</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>mariadb</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>testcontainers</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.testng</groupId>
+            <artifactId>testng</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>

plugin/trino-mariadb/src/main/java/io/trino/plugin/mariadb/ImplementAvgBigint.java

@@ -0,0 +1,26 @@
+/*
+ * Licensed 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 io.trino.plugin.mariadb;
+
+import io.trino.plugin.jdbc.aggregation.BaseImplementAvgBigint;
+
+public class ImplementAvgBigint
+        extends BaseImplementAvgBigint
+{
+    @Override
+    protected String getRewriteFormatExpression()
+    {
+        return "avg((%s * 1.0))";
+    }
+}