ML Engine Connector Properties | Teradata Vantage - 2.2.2 - ML Engine Connector Properties - Teradata Vantage - Teradata Vantage on AWS

Teradata Vantage™ User Guide

Product
Teradata Vantage
Teradata Vantage on AWS
Release Number
2.2.2
Release Date
April 2021
Content Type
User Guide
Publication ID
B700-4002-041K
Language
English (United States)

In Teradata Vantage, the Teradata QueryGrid™ fabric is configured for internal communication. Two Teradata QueryGrid links are created to facilitate communication between Advanced SQL Engine and ML Engine.

QueryGrid Manager shows the properties that you can configure. Vantage requires that some property defaults cannot be changed.

ML Engine connector properties are:

Name Default Description Connector Type Change Default
Authentication Mechanism Trusted Authentication mechanism used to log on to ML Engine. Target No
Column Name Handling CASE-INSENSITIVE Controls whether ML Engine will attempt to treat column names as case-insensitive. Target Yes
Connection Evict Frequency 1 minute Frequency of eviction checks. It checks, closes, and removes the connection object from the pool if the idle time (current time - last time of use) of connection object is greater than connectionMaxIdleTime/sessionConnectionMaxIdleTime. It can be reduced if there are multiple concurrent users running queries and due to high demand, the connections should be freed up more frequently for new users to pick up. Target Yes
Connection Max Idle Time 1800 seconds Maximum idle time for connection cache object, after which it is closed and evicted from the cache. It should be used if there are multiple concurrent users/queries running on the system that might lead to starvation of connection objects. Target Yes
Connection Pool Size 100 Maximum number of connection objects that can be stored in the connection pool. When trying to acquire a new connection, the connector checks for entry to be made available in the connection pool or else it fails after 5 minutes. There is one connection pool per connector config, including the username. This can be used to throttle the number of connections that can be established by concurrent queries for one user. Target Yes
Database Name beehive Database name for ML Engine. Target No
Default String Size 32000 VARCHAR truncation size (size at which data imported from, or exported to, string columns is truncated). Value represents maximum number of Unicode characters to import. Initiator, Target Yes
Enable Blob Support TRUE Enables support of BLOB datatype. Initiator, Target No
Enable Clob Support TRUE Enables support of CLOB datatype. Initiator, Target Yes
Enable Logging INFO Logging level for connector or link properties. Applies to both initiating and target connector; however, if their levels are different, level for initiating connector takes precedence. Initiator, Target Yes
In-Memory Result TRUE Whether to use in-memory tables for primary function results imported to the Advanced SQL Engine. Target No
In-Memory Input TRUE Whether to use in-memory tables for data exported to Advanced SQL Engine for input to functions. Target No
Large Blob Handling ERROR Action to take if BLOB larger than 10485760 is exported to ML Engine: ERROR causes exception to be raised; TRUNCATE causes data to be truncated to 10485760.

To change this behavior in Advanced SQL Engine session, include statement such as:

set foreign server attr = 'servername=coprocessor;largeBlobHandling=TRUNCATE;' for session volatile;

  Yes
Large Clob Handling ERROR Action to take if CLOB larger than 10485760 is exported to ML Engine: ERROR causes exception to be raised; TRUNCATE causes data to be truncated to 10485760.

To change this behavior in Advanced SQL Engine session, include statement such as:

set foreign server attr = 'servername=coprocessor;largeClobHandling=TRUNCATE;' for session volatile;

Initiator, Target Yes
Link Buffer Count 4 Maximum number of write buffers available on a single channel at one time. Initiator, Target Yes
Link Buffer Size 1048576 Maximum size of the write buffers to allocate for row handling and message exchange. Initiator Yes
Link Heartbeat Interval 60000 Maximum interval in milliseconds for heartbeat signal on channel between connector and fabric instance, used for health check status. This interval must be greater than Link Handshake Timeout. Initiator, Target Yes
Link Handshake Timeout 30000 Handshake timeout in milliseconds for link channel setup. Initiator, Target Yes
Oldest Active Session 24 No connection older than this value (in hours) will be used to begin executing a query on ML Engine. Target No
Password   The password for User Name. Target Yes
Port 30002 Port number of ML Engine server. Target No
Read Timeout 30000 Number of milliseconds to wait to read between data packets when importing data messages. Initiator, Target Yes
Regex to limit Retained Tables .* Regex applied to the exception toString() value using class java.util.regex.Pattern. The tables are retained only when there is a match. If there is any exception or error applying the regex, the tables will not be retained. This property is applied only when the Retain Tables On Error property is set to TRUE.

Use this property only as directed by your Customer Service Representative.

Target No
Response Timeout 1800000 Number of milliseconds to wait for final data exec response when all data has been transferred. Initiator, Target Yes
Retain Tables On Error FALSE Check the box to set to true and enable table retention on error.

Use this property only as directed by your Customer Service Representative.

Target No
Reverse Link Name teradata_link The name of the link that has ML Engine connector as the initiator and Advanced SQL Engine connector as the target. Target Yes
Schema Name none Default schema name. Target Yes
Server Configured specifically to your environment Hostname of ML Engine server. Target No
Transformformatting FALSE Whether to transform array columns to Teradata string format. If FALSE, array columns are returned in JSON format, except those specified in RETURN clause to be returned in Teradata string format. Initiator, Target Yes
User Name beehive Value to use when initiator does not support mechanism to provide user credentials. Value is also used for connectivity diagnostic checks. Target No
Write Timeout 30000 Number of milliseconds to wait to write between data packets when exporting data messages. Initiator, Target Yes