In this chapter, we'll describe the fourth essential CLI resource: the desc.
We have much to say about:
- What is in a
desc— fields of the header and the "item descriptor areas". - How to make a
desc, or how to use an automatically-madedesc. - Similarities and differences of ARDs, APDs, IRDs and IPDs.
- Functions which attack
descs directly:SQLAllocHandle,SQLGetDescField,SQLSetDescField,SQLGetDescRec,SQLSetDescRec,SQLCopyDescand others. - Functions which attack
descs indirectly:SQLBindParameter,SQLBindCol,SQLColAttribute,SQLDescribeColand others.
-
Descriptor Areas
Here is a piece of CLI code: SQLExecDirect(hstmt,"SELECT col_1,col_2 FROM T... -
Automatic descs
There are four automatic descs; here's a brief description of each: IRD, or... -
The desc Fields
On first reading, we suggest that you skip quickly through this section. Bu... -
The desc Header Fields
There are five desc header fields: SQL_DESC_ALLOC_TYPE, SQL_DESC_COUNT, SQL... -
The desc Item Descriptor Area (IDA) Fields
There are 28 desc IDA fields: None SQL_DESC_CHARACTER_SET_CATALOGSQL_DESC_C... -
The desc Functions
We are now ready to describe the individual desc functions. There is a good...
