The mi_scan_nprojs() accessor function

The mi_scan_nprojs() function returns a value that is 1 less than the number of columns in a query projection.

Syntax

mi_integer  mi_scan_nprojs(MI_AM_SCAN_DESC *scanDesc)
scanDesc
Points to the scan descriptor.

Usage

Use the return value from this function to determine the number of times to loop through the related mi_scan_projs() function.

The mi_scan_nprojs() function returns 2 to indicate that the following SELECT statement projects three columns: 
SELECT column1, column2, column3 FROM table

Return values

The integer return value indicates the number of columns that the Projection clause of a query specifies.