16.20 - SQL Descriptor Fields - ODBC Driver for Teradata

ODBC Driver for Teradata® User Guide

ODBC Driver for Teradata
October 2018
User Guide

The following descriptor fields are exposed by ODBC Driver for Teradata:

  • SQL_DESC_TD_ACTIVITY_TYPE is an SQLINTEGER that indicates the type of SQL statement that was executed.
  • SQL_DESC_TD_COST_ESTIMATE is an SQLINTEGER with a cost estimate for running the SQL statement. The value returned is the time estimate in seconds.
  • SQL_DESC_TD_FORMAT is a character string which is the Teradata FORMAT column.
  • SQL_DESC_TD_ACTUAL_NAME is a character string containing the column name associated with the result column.
  • SQL_DESC_TD_CHARACTER_SET is an SQLINTEGER that contains the character set of a given column. Values are:

      If both the Extended Statement Information and LOB support options are disabled, the ODBC driver is unable to determine the server character set, resulting in the return value SQL_TD_CS_UNDEFINED.

  • SQL_DESC_TD_EXPORT_WIDTH is an SQLINTEGER that contains the database export width for character columns, while SQL_DESC_TD_EXPORT_WIDTH_ADJ is an SQLINTEGER that contains the database export width adjustment for character columns.

    These fields are only valid if the column character set is different from SQL_TD_CS_UNDEFINED; otherwise they have the value -1, which indicates an undefined value.

    The fields can be used to calculate the number of bytes exported by Teradata Database for a given character column. The formula is:

    <Number of bytes > = <export width * N > + <export width adjustment>

    where N is the number of characters in the column.

  • SQL_DESC_TD_EXPORT_BYTES is an SQLINTEGER that contains the number of bytes the database provides for a character column.
  • SQL_DESC_TD_ODBC_TYPE is an SQLSMALLINT that contains the Teradata ODBC-specific SQL data type code. If multiple database types have the same standard ODBC SQL type, then the Teradata ODBC-specific SQL data type code can be used to distinguish between the types. For Example, see Number Data Types.