16.10 - Get Row - Parallel Transporter

Teradata Parallel Transporter Operator Programmer Guide

prodname
Parallel Transporter
vrm_release
16.10
created_date
May 2017
category
Programming Reference
featnum
B035-2435-057K

Purpose

Get Row is the service function that retrieves a data row.

Structure

#include <pxoper.h>
PXSTC_Code PX_GetRow(PX_TableSchemaHandle  tableSchemaHandle,
   PX_Count *  columnCount,
   PX_Indicator **  nullIndicator,
   PX_ByteOffset **  offsets,
   PX_Length **  lengths,
   PX_Addr *  rowAddr,
   PX_Length *  rowLength);

where the following is true:

Parameter Function Specification
columnCount output Pointer to the number of columns associated with the data row.
lengths output Pointer to the array of integers representing the length of the corresponding column value.
nullIndicator output Pointer to the array of indicator bytes specifying whether or not the corresponding column value is NULL.
offsets output Pointer to the array of integers representing the corresponding column positions in terms of the number of bytes into the data row.
rowAddr output Pointer to the address of the data row.
rowLength output Pointer to the length of the data row.
tableSchemaHandle input Table schema handle by which the data row is to be obtained.

Return Codes

The following Get Row function status codes are defined by the Teradata PT operator interface.

Status Code Signifies
PXSTC_BadHandle An undefined data schema handle.
PXSTC_Success Successful retrieval of the data row.
PXSTC_EndOfData End of data.

Usage Notes

Consider the following when defining the Get Row function.

Topic Usage Notes
Return Data Format Data rows returned by the Get Row function are always prefixed with NULL indicator bytes.
Status If the function status is PXSTC_Success:
  • The rowAddr parameter stores the address of the data row.
  • The rowLength parameter stores the length of the data row.
  • The columnCount parameter stores the number of columns associated with the data row.
  • The nullIndicators parameter is the address of the array indicating whether or not the column values are NULL.
  • The offsets parameter is the address of the array that indicates the byte offsets into the data row.
  • The lengths parameter is the address of the array that indicates the lengths of the column values.
See Also