16.20 - Inhibit-buffer-expansion - Teradata Tools and Utilities

Teradata® Call-Level Interface Version 2 Reference for Mainframe-Attached Systems

prodname
Teradata Tools and Utilities
vrm_release
16.20
created_date
September 2019
category
Programming Reference
featnum
B035-2417-108K

Inhibit-buffer-expansion specifies whether CLIv2 can automatically increase the Fetch-maximum-data-length value, unless prevented by the DBCAREA Maximum-parcel and APH-response-OK options. By default, if the Teradata Database indicates that a response parcel to be fetched exceeds Fetch-maximum-data-length, CLIv2 will allocate a larger response buffer to receive a response parcel.

This option would rarely be used by a production application. One use would be if a response parcel larger than the Fetch-maximum-data-length value was unacceptable for some reason. During development, this option might be used iteratively to ascertain the size of the largest response parcel so that the Fetch-maximum-data-length value could be set to avoid buffer expansion to optimize performance.

Inhibit-buffer-expansion exists only when DBCHINI had been called for a DBCAREA with Total-length set to at least 1024 (that is, the returned DBCAREA Level field is set to at least 2). For a smaller DBCAREA, Inhibit-buffer-expansion is assumed to be 'N'.

In this language... The value is...
COBOL INHIBIT-BUFFER-EXPANSION
PL/I INHIBIT_BUFFER_EXPANSION
C, C++ inhibitBufferExpansion
IBM Assembler DBRIIBE
This routine... Does this for Inhibit-buffer-expansion...
DBCHINI writes
DBCHCL reads (RSUP; IRQ; IWPF reads (RSUP; IRQ; IWPF)
Inhibit-buffer-expansion is used by... To...
applications write

One of the following values may be set before initiating a request.

If the previously processed response... Then set Inhibit-buffer-expansion to...
indicates that if necessary, CLIv2 will allocate a larger buffer to receive a response parcel. 'N', the default, using one of the following mnemonics:
  • For COBOL, DBC-NO
  • For PL/I, DBC_INHIBIT_BUFF_EXP_NO
  • For C, DBC_InhibitBuffExpNo
  • For IBM Assembler, DBRIIBEN
indicates that CLIv2 will not allocate a larger buffer to receive a response parcel. 'Y', using one of the following mnemonics:
  • For COBOL, DBC-YES
  • For PL/I, DBC_INHIBIT_BUFF_EXP_YES
  • For C, DBC_InhibitBuffExpYes
  • For IBM Assembler, DBRIIBEY