Note: At present, this section is just taken from PostgreSQL documentation and is subject to revision for Postgres-XC.
SPI_fnumber
returns the column number for the
column with the specified name.
If colname refers to a system column (e.g., oid) then the appropriate negative column number will be returned. The caller should be careful to test the return value for exact equality to SPI_ERROR_NOATTRIBUTE to detect an error; testing the result for less than or equal to 0 is not correct unless system columns should be rejected.
Note: At present, this section is just taken from PostgreSQL documentation and is subject to revision for Postgres-XC.
input row description
column name