17.20 - Statement Options Set in SQLSetStmtAttr() - 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 following table lists the Statement Options in SQLSetStmtAttr().

Statement Support
SQL_ATTR_ASYNC_ENABLE Supported
SQL_ATTR_METADATA_ID Supported
SQL_ATTR_REDRIVE Supported.

If Redrive is turned on for a session, it can be turned off for a particular statement. If redrive is turned OFF at the session level it cannot be turned ON for a statement.

SQL_ATTR_REDRIVE (13014) statement attribute can take

SQL_REDRIVE_OFF (0) and SQL_REDRIVE_ON (1) values.

SQL_BIND_TYPE Only supports SQL_BIND_BY_COLUMN
SQL_CONCURRENCY Only supports SQL CONCUR_READ_ONLY
SQL_ATTR_CONNECTION_POOLING Supports SQL_CP_PER_DRIVER, SQL_CP_ONE_PER_HENV, and SQL_CP_OFF
SQL_CURSOR_TYPE Only supports SQL_CURSOR_FORWARD_ONLY
SQL_KEYSET_SIZE Only supports SQL_KEYSET_SIZE=0
SQL_MAX_LENGTH Not supported
SQL_MAX_ROWS Supported

SQL_MAX_ROWS confines the results returned to a user-specified limit. This is implemented on a per SELECT statement basis and as such, might not reduce the network traffic for multi-statement requests due to the Teradata mechanism used for spool control.

In multi-statement requests, network traffic cannot be avoided since the current result set must be scrolled through to get to the next.

In single-statement requests or if within the last statement of a multi-statement request, canceling the request reduces network traffic.

Reduce network traffic by fetching only the needed result rows of data. If all of the results from a single-statement request or from the last statement of a multi-statement request are not needed, calling SQLFreeSTMT(SQL_CLOSE) discards all pending results.

SQL_NOSCAN Supported

The implementation of SQL_NOSCAN varies slightly from the ODBC definition. By default, requests are scanned (parsed) to convert ODBC SQL syntax to Teradata SQL syntax.

If an application calls SQLSetStmtOption(hstmt, SQL_NOSCAN, SQL_NOSCAN_ON), ODBC Driver for Teradata does not parse SQL requests. The ODBC SDK mentions that only ODBC escape clauses are not scanned when SQL_NOSCAN_ON is set.

For custom ODBC applications that generate only Teradata-specific SQL, set SQL_NOSCAN_ON to avoid parsing SQL requests and to improve performance.

SQL_QUERY_TIMEOUT Supported
SQL_RETRIEVE_DATA Only supports SQL_RD_ON
SQL_ROWSET_SIZE Only supports SQL_ROWSET_SIZE=1
SQL_SIMULATE_CURSOR Only supports SQL_SC_NON_UNIQUE
SQL_USE_BOOKMARKS Not supported