Synopsis
SPI_execp(plan,
values,
nulls,
tcount)
Inputs
- void *plan
 Execution plan
- Datum *values
 Actual parameter values
- char *nulls
 Array describing which parameters are NULLs
| n indicates NULL (values[] entry ignored) | 
| space indicates not NULL (values[] entry is valid) | 
- int tcount
 Number of tuples for which plan is to be executed
Outputs
- int
    Returns the same value as SPI_exec as well as
|  SPI_ERROR_ARGUMENT
 if plan
 is NULL or tcount < 0 | 
|    SPI_ERROR_PARAM
 if values
 is NULL
 and plan
 was prepared with some parameters. | 
- SPI_tuptable
 initialized as in
   SPI_exec if successful
- SPI_processed
 initialized as in
   SPI_exec if successful