Federated MariaDB Enterprise Spider Topology

Overview

In the Federated MariaDB Enterprise Spider topology, a Spider Node contains one or more "virtual" Spider Tables. A Spider Table does not store data. When a Spider Table is queried, the Enterprise Spider storage engine uses a MariaDB foreign data wrapper to read from and write to a Data Table on a Data Node.

Benefits

MariaDB Enterprise Spider:

The Spider Federated topology:

  • Can be used to query tables located on a different MariaDB Enterprise Server node from the Spider Node using the MariaDB foreign data wrapper.

  • Can be used to join tables located on a different MariaDB Enterprise Server node with tables on the Spider Node using the MariaDB foreign data wrapper.

  • Can be used to migrate tables located on a different MariaDB Enterprise Server node to the Spider Node using the MariaDB foreign data wrapper.

Federated MariaDB Enterprise Spider Topology

Spider Federated Topology

In the Spider Federated topology, a Spider Node contains one or more "virtual" Spider Tables. A Spider Table does not store data. When a Spider Table is queried, the Enterprise Spider storage engine uses a MariaDB foreign data wrapper to read from and write to a Data Table on a Data Node.

The Spider Federated topology consists of:

  • One MariaDB Enterprise Server node is a Spider Node

  • One MariaDB Enterprise Server node is a Data Node

The Spider Node:

  • Contains one or more Spider Tables

  • Uses the Enterprise Spider storage engine plugin for Spider Tables

  • Uses a MariaDB foreign data wrapper to query the Data Table on the Data Node

The Data Node:

  • Contains a Data Table for each Spider Table

  • Uses a non-Spider storage engine for each Data Table, such as InnoDB or ColumnStore

Term Definitions

Term

Definition

Data Node

A Data Node is a MariaDB Enterprise Server node that contains one or more Data Tables.

Data Table

A Data Table stores data for a Spider Table. When a Spider Table is queried, the Enterprise Spider storage engine uses the MariaDB foreign data wrapper to read from and write to the Data Table on a Data Node. The Data Table must be created on the Data Node with the same structure as the Spider Table. The Data Table must use a non-Spider storage engine, such as InnoDB or ColumnStore.

ODBC Data Source

An ODBC Data Source relies on an ODBC Driver and an ODBC Driver Manager to query an external data source.

ODBC Driver

An ODBC Driver is a library that integrates with a ODBC Driver Manager to query an external data source.

ODBC Driver Manager

An ODBC Driver Manager allows applications to use ODBC Drivers.

Spider Node

A Spider Node is a MariaDB Enterprise Server node that contains one or more Spider Tables.

Spider Table

A Spider Table is a virtual table that does not store data. When a Spider Table is queried, the Enterprise Spider storage engine uses foreign data wrappers to read from and write to Data Tables on Data Nodes or ODBC Data Sources.

Example Use Cases

Query MariaDB Enterprise Server Nodes

The Spider Federated topology can be used to query tables located on another MariaDB Enterprise Server node:

  • The MariaDB Enterprise Server node with the desired table is configured as a Data Node.

  • The MariaDB Enterprise Server node that needs to query the table is configured as a Spider Node.

  • The Data Table is the desired table on the Data Node.

  • A Spider Table is created on the Spider Node that references the Data Table on the Data Node.

  • On the Spider Node, the Data Table is queried by querying the Spider Table like the following:

    SELECT * FROM spider_tab;

  • Non-Spider tables can also be referenced in queries with the Spider Table:

    SELECT *
FROM spider_tab s
JOIN innodb_tab i
ON s.id=i.id;

Migrate Tables from MariaDB Enterprise Server Nodes

The Spider Federated topology can be used to migrate tables from one MariaDB Enterprise Server node to another MariaDB Enterprise Server node:

  • The MariaDB Enterprise Server node with the source table is configured as a Data Node.

  • The MariaDB Enterprise Server node with the destination table is configured as a Spider Node.

  • The Data Table is the source table on the Data Node.

  • A Spider Table is created on the Spider Node that references the Data Table on the Data Node.

  • On the Spider node, the Data Table's data is migrated to the destination table by querying the Spider Table like the following:

    INSERT INTO innodb_tab
   SELECT * FROM spider_tab;

Examples

Load Spider with Configuration File (ES 10.4+)

[mariadb]
...
plugin_load_add = "ha_spider"

Load Spider with INSTALL SONAME (ES 10.4+)

INSTALL SONAME "ha_spider";

Load Spider with Script (ES 10.3)

$ mysql --user root --password < /usr/share/mysql/install_spider.sql

View Foreign Data Wrappers (ES 10.5+)

SELECT * FROM information_schema.SPIDER_WRAPPER_PROTOCOLS;

Create Federated Spider Table

CREATE SERVER hq_server
FOREIGN DATA WRAPPER mariadb
OPTIONS (
   HOST "192.0.2.2",
   PORT 5801,
   USER "spider_user",
   PASSWORD "password",
   DATABASE "hq_sales"
);

CREATE DATABASE spider_hq_sales;

CREATE TABLE spider_hq_sales.invoices (
   branch_id INT NOT NULL,
   invoice_id INT NOT NULL,
   customer_id INT,
   invoice_date DATETIME(6),
   invoice_total DECIMAL(13, 2),
   payment_method ENUM('NONE', 'CASH', 'WIRE_TRANSFER', 'CREDIT_CARD', 'GIFT_CARD'),
   PRIMARY KEY(branch_id, invoice_id)
) ENGINE=Spider
COMMENT='server "hq_server", table "invoices"';