17.20 - ODBC FastExport - ODBC Driver for Teradata

ODBC Driver for Teradata® User Guide

Product
ODBC Driver for Teradata
Release Number
17.20
Published
June 2022
Language
English (United States)
Last Update
2022-06-21
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The FastExport protocol is a Vantage feature that improves the performance of SELECT statements that meet certain criteria, enabling you to quickly retrieve large amounts of data. The exact difference in performance varies depending on the application and database configuration, and may be affected by the structure of the query. For example, FastExport works best for queries that do not include any GROUP BY or ORDER BY clauses.

Because the FastExport protocol might return result sets in a different order compared to when the standard protocol is used, in some cases you must use an ORDER BY clause to enforce a specific result set order. For example, without an ORDER BY clause, a query that contains an ordered analytic function might not produce the expected ordered result set.
When connected to a database that supports FastExport, ODBC Driver for Teradata can use the protocol to improve the performance of SELECT queries that meet the following criteria:
  • The table or view being queried does not include any data types that the FastExport protocol does not support. For example, BLOB and CLOB data are not supported.
  • The query is being run as a prepared statement, using SQLPrepare and SQLExecute. SQLExecDirect queries are not supported.
  • If the query is written as multiple semicolon-separated statements, the statements must all be SELECT statements.

Additionally, if you are running more than one prepared statement at the same time, the statements are subject to certain limitations. For more information, see "Restrictions and Limitations" in Teradata® FastExport Reference, B035-2410.

To configure the driver to use the FastExport protocol, set the following properties in your DSN or connection string. For more information, see Teradata DSN Options.

Key Names Supporting ODBC FastExport
Key Name Default Value Required
Type Default No
Sessions None No