When USING-data-pointer-vector is not zero, USING-data-pointer-vector is a four byte pointer to a vector of pointers to data that is referred to by the USING row descriptor in the request string. When Varying-length-request is not specified, the lengths of the data are specified by corresponding entries in the USING-data-length-vector. When Varying-length-request is specified, the length of the data precedes the data itself. The number of entries in the list is given by USING-data-count.
USING-data-pointer-vector exists only when DBCHINI had been called for a DBCAREA with Total-length set to at least 640 (that is, the returned DBCAREA Level value is at least 1). For a smaller DBCAREA, USING-data-pointer-vector is ignored.
|In this language...||The variable name for ]USING-data-pointer-vector is...|
|This routine...||Does this for USING-data-pointer-vector...|
|DBCHCL||reads (RSUP; IWPF; IRQ)|
|USING-data-pointer-vector is used by...||To...|
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 Varying-length-request will be set to either of the following:
|When Varying-length-request is set to this value...||Then...|
|Y||the USING-data-length-vector is ignored and the each data area addressed by USING data-pointer-vector 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 the entries of USING-data-length-vector.|
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 the using-data appropriately. The maximum number of fields in the Teradata SQL USING row descriptor may be obtained using the DBCHQE SQL-limits query.
|IF the data...||THEN the application...|
|cannot contain nulls||sets Use-presence-bits to N in the DBCAREA.|
|can contain nulls||inserts bytes containing indicator bits at the front of the data string and sets Use-presence-bits to 'Y'. See Use-presence-bits.
The application does the following, depending on the setting:
If there is no USING row descriptor in the request string, set USING-data-count to zero.