Using Data Length is a four byte field that has three meanings, relating to the following:
In this language... |
The variable name for Using Data Length is... |
COBOL |
DBCAREA‑USING‑DATA‑LEN |
PL/I |
USING_DATA_LEN |
C |
using_data_len |
IBM Assembler |
DBRIUDL |
This routine... |
Does this for Using Data Length... |
DBCHINI |
writes |
DBCHCL |
reads (IRQ; IWPF) |
Using Data Length is used by... |
To... |
applications |
write |
The value of Using Data Length must be positive, with a maximum value of approximately. . . |
If Maximum Parcel is set to... |
32763 |
O |
65531 |
H |
The actual maximum may vary slightly with the version of the Teradata Database being used; the value may be obtained using the DBCHQE CLIv2-limits query
Before calling DBCHCL for the Initiate Request function and if the request contains a USING row descriptor, the application must build a data string.
The data string must contain the data described by the USING row descriptor, and the Variable Length Request will be set to either of the following:
When Variable Length Request is set to this value... |
Then... |
Y |
the Using Data Length field is ignored and the Using Data Pointer must point to the two‑byte area containing the length of the using data string, which is followed by the actual using data string. |
N |
the application must supply the length information in Using Data Length |
See “Variable Length Request” on page 197.
Since DBCHCL does not parse the request string, it is the application‘s responsibility to check whether the request string contains a USING row descriptor and then to set Using Data Length appropriately.