SPI_fnumber
Name
SPI_fnumber -- Finds the attribute number for specified attribute name
Synopsis
SPI_fnumber(tupdesc, fname)
Inputs
- TupleDesc tupdesc
- Input tuple description 
- char * fname
- Field name 
Outputs
- int
- Attribute number
 | Valid one-based index number of attribute |  | SPI_ERROR_NOATTRIBUTE if the named attribute is not found |  
 
Description
SPI_fnumber 
   returns the attribute number for the attribute with name in fname.
Usage
Attribute numbers are 1 based.
If the given fname refers to a system attribute (eg, oid)
then the appropriate negative attribute number will be returned.
The caller should be careful to test for exact equality to 
SPI_ERROR_NOATTRIBUTE to detect error;
testing for result <= 0 is not correct unless system attributes
should be rejected.