SingleStore connector

The SingleStore (formerly known as MemSQL) connector allows querying and creating tables in an external SingleStore database.

Requirements

To connect to SingleStore, you need:

• SingleStore version 8.7 or higher.
• Network access from the Trino coordinator and workers to SingleStore. Port 3306 is the default port.

(singlestore-configuration)=

Configuration

To configure the SingleStore connector, create a catalog properties file in etc/catalog named, for example, example.properties, to mount the SingleStore connector as the example catalog. Create the file with the following contents, replacing the connection properties as appropriate for your setup:

connector.name=singlestore
connection-url=jdbc:singlestore://example.net:3306
connection-user=root
connection-password=secret

The connection-url defines the connection information and parameters to pass to the SingleStore JDBC driver. The supported parameters for the URL are available in the SingleStore JDBC driver documentation.

The connection-user and connection-password are typically required and determine the user credentials for the connection, often a service user. You can use {doc}secrets </security/secrets> to avoid actual values in the catalog properties files.

(singlestore-tls)=

Connection security

If you have TLS configured with a globally-trusted certificate installed on your data source, you can enable TLS between your cluster and the data source by appending a parameter to the JDBC connection string set in the connection-url catalog configuration property.

Enable TLS between your cluster and SingleStore by appending the useSsl=true parameter to the connection-url configuration property:

connection-url=jdbc:singlestore://example.net:3306/?useSsl=true

For more information on TLS configuration options, see the JDBC driver documentation.

Multiple SingleStore servers

You can have as many catalogs as you need, so if you have additional SingleStore servers, simply add another properties file to etc/catalog with a different name (making sure it ends in .properties). For example, if you name the property file sales.properties, Trino will create a catalog named sales using the configured connector.

Querying SingleStore

The SingleStore connector provides a schema for every SingleStore database. You can see the available SingleStore databases by running SHOW SCHEMAS:

SHOW SCHEMAS FROM example;

If you have a SingleStore database named web, you can view the tables in this database by running SHOW TABLES:

SHOW TABLES FROM example.web;

You can see a list of the columns in the clicks table in the web database using either of the following:

DESCRIBE example.web.clicks;
SHOW COLUMNS FROM example.web.clicks;

Finally, you can access the clicks table in the web database:

SELECT * FROM example.web.clicks;

If you used a different name for your catalog properties file, use that catalog name instead of example in the above examples.

(singlestore-type-mapping)=

Type mapping

Because Trino and Singlestore each support types that the other does not, this connector {ref}modifies some types <type-mapping-overview> when reading or writing data. Data types may not map the same way in both directions between Trino and the data source. Refer to the following sections for type mapping in each direction.

Singlestore to Trino type mapping

The connector maps Singlestore types to the corresponding Trino types following this table:

:::{list-table} Singlestore to Trino type mapping :widths: 30, 30, 40 :header-rows: 1

• • Singlestore type
  • Trino type
  • Notes
• • BIT
  • BOOLEAN
• • BOOLEAN
  • BOOLEAN
• • TINYINT
  • TINYINT
• • TINYINT UNSIGNED
  • SMALLINT
• • SMALLINT
  • SMALLINT
• • SMALLINT UNSIGNED
  • INTEGER
• • INTEGER
  • INTEGER
• • INTEGER UNSIGNED
  • BIGINT
• • BIGINT
  • BIGINT
• • BIGINT UNSIGNED
  • DECIMAL(20, 0)
• • DOUBLE
  • DOUBLE
• • REAL
  • DOUBLE
• • DECIMAL(p, s)
  • DECIMAL(p, s) or NUMBER
  • Maps to Trino DECIMAL when p ≤ 38. Otherwise, maps to NUMBER.
• • CHAR(n)
  • CHAR(n)
• • TINYTEXT
  • VARCHAR(255)
• • TEXT
  • VARCHAR(65535)
• • MEDIUMTEXT
  • VARCHAR(16777215)
• • LONGTEXT
  • VARCHAR
• • VARCHAR(n)
  • VARCHAR(n)
• • LONGBLOB
  • VARBINARY
• • DATE
  • DATE
• • TIME
  • TIME(0)
• • TIME(6)
  • TIME(6)
• • DATETIME
  • TIMESTAMP(0)
• • DATETIME(6)
  • TIMESTAMP(6)
• • JSON
  • JSON

:::

No other types are supported.

Trino to Singlestore type mapping

The connector maps Trino types to the corresponding Singlestore types following this table:

:::{list-table} Trino to Singlestore type mapping :widths: 30, 30, 40 :header-rows: 1

• • Trino type
  • Singlestore type
  • Notes
• • BOOLEAN
  • BOOLEAN
• • TINYINT
  • TINYINT
• • SMALLINT
  • SMALLINT
• • INTEGER
  • INTEGER
• • BIGINT
  • BIGINT
• • DOUBLE
  • DOUBLE
• • REAL
  • FLOAT
• • DECIMAL(p, s)
  • DECIMAL(p, s)
• • CHAR(n)
  • CHAR(n)
• • VARCHAR(65535)
  • TEXT
• • VARCHAR(16777215)
  • MEDIUMTEXT
• • VARCHAR
  • LONGTEXT
• • VARCHAR(n)
  • VARCHAR(n)
• • VARBINARY
  • LONGBLOB
• • DATE
  • DATE
• • TIME(0)
  • TIME
• • TIME(6)
  • TIME(6)
• • TIMESTAMP(0)
  • DATETIME
• • TIMESTAMP(6)
  • DATETIME(6)
• • JSON
  • JSON

:::

No other types are supported.

(singlestore-sql-support)=

SQL support

The connector provides read access and write access to data and metadata in a SingleStore 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:

• , see also
• , see also
• , see also
• , see also

(singlestore-insert)=

(singlestore-update)=

(singlestore-delete)=

(singlestore-alter-table)=

(singlestore-procedures)=

Procedures

Performance

The connector includes a number of performance improvements, detailed in the following sections.

(singlestore-pushdown)=

Pushdown

The connector supports pushdown for a number of operations:

• {ref}join-pushdown
• {ref}limit-pushdown
• {ref}topn-pushdown