12.21. SQL Server Connector
The SQL Server connector allows querying and creating tables in an external SQL Server database. This can be used to join data between different systems like SQL Server and Hive, or between two different SQL Server instances.
To configure the SQL Server connector, create a catalog properties file
etc/catalog named, for example,
mount the SQL Server connector as the
Create the file with the following contents, replacing the
connection properties as appropriate for your setup:
connector.name=sqlserver connection-url=jdbc:sqlserver://[serverName[\instanceName][:portNumber]] connection-user=root connection-password=secret
Multiple SQL Server Databases or Servers
The SQL Server connector can only access a single database within a SQL Server server. Thus, if you have multiple SQL Server databases, or want to connect to multiple instances of the SQL Server, you must configure multiple catalogs, one for each instance.
To add another catalog, simply add another properties file to
with a different name (making sure it ends in
.properties). For example,
if you name the property file
sales.properties, Presto will create a
sales using the configured connector.
Querying SQL Server
The SQL Server connector provides access to all schemas visible to the specified user in the configured database.
For the following examples, assume the SQL Server catalog is
You can see the available schemas by running
SHOW SCHEMAS FROM sqlserver;
If you have a schema named
web, you can view the tables
in this schema by running
SHOW TABLES FROM sqlserver.web;
You can see a list of the columns in the
clicks table in the
using either of the following:
DESCRIBE sqlserver.web.clicks; SHOW COLUMNS FROM sqlserver.web.clicks;
Finally, you can query the
clicks table in the
SELECT * FROM sqlserver.web.clicks;
If you used a different name for your catalog properties file, use
that catalog name instead of
sqlserver in the above examples.
SQL Server connector supports user impersonation. Please see User Impersonation for more details.
User impersonation can be turned with:
User impersonation in SQL Server connector is based on
EXECUTE AS USER.
For more details please visit: docs.microsoft.com.
SQL Server connector supports table and column statistics. The statistics are collected by SQL Server Database and retrieved by the connector. Currently, the connector can use information stored in single-column statistics. SQL Server Database can automatically create column statistics for certain columns. If column statistics were not created automatically for a certain column, you can create them by executing the following statement in SQL Server Database.
CREATE STATISTICS my_statistics_name ON table_schema.table_name (column_name);
SQL Server Database routinely updates the statistics. In some cases, you may want to force statistics update (e.g. after defining new column statistics or after changing data in the table). You can do that by executing the following statement in SQL Server Database.
UPDATE STATISTICS table_schema.table_name;
Please refer to SQL Server documentation for information about options, limitations and additional considerations.
Table Statistics Configuration Properties
||Enables table and column statistics.||
||Duration for which table and column statistics are cached.||
||Cache the fact that table statistics were not available.||
SQL Server Connector Limitations
Presto supports connecting to SQL Server 2016, SQL Server 2014, SQL Server 2012 and Azure SQL Database.
Presto supports the following SQL Server data types. The following table shows the mappings between SQL Server and Presto data types.
|SQL Server Type||Presto Type|
Complete list of SQL Server data types.
The following SQL statements are not yet supported: