The mi_scan_quals() accessor function
The mi_scan_quals() function returns the qualification descriptor, which describes the conditions that an entry must satisfy to qualify for selection.
Syntax
MI_AM_QUAL_DESC* mi_scan_quals(MI_AM_SCAN_DESC *scanDesc);- scanDesc
- Points to the scan descriptor.
Usage
The am_getnext purpose
function calls mi_scan_quals() to obtain the starting
point from which it evaluates a row and then passes the return value
(a pointer) from this function to all the qualification-descriptor
accessor functions.
Important: If this function returns
a NULL-valued pointer, the access method sequentially scans the table
and returns all rows.
Return values
A valid pointer indicates the start of the qualification descriptor for this scan. A NULL-valued pointer indicates that the access method should return all rows.