SPI_modifytuple — create a row by replacing selected fields of a given row
HeapTuple SPI_modifytuple(Relationrel, HeapTuplerow, intncols, int *colnum, Datum *values, const char *nulls)
SPI_modifytuple creates a new row by
substituting new values for selected columns, copying the original
row's columns at other positions. The input row is not modified.
The new row is returned in the upper executor context.
This function can only be used while connected to SPI.
Otherwise, it returns NULL and sets SPI_result to
SPI_ERROR_UNCONNECTED.
Relation relUsed only as the source of the row descriptor for the row. (Passing a relation rather than a row descriptor is a misfeature.)
HeapTuple rowrow to be modified
int ncolsnumber of columns to be changed
int * colnum an array of length ncols, containing the numbers
of the columns that are to be changed (column numbers start at 1)
Datum * values an array of length ncols, containing the
new values for the specified columns
const char * nulls an array of length ncols, describing which
new values are null
If nulls is NULL then
SPI_modifytuple assumes that no new values
are null. Otherwise, each entry of the nulls
array should be ' ' if the corresponding new value is
non-null, or 'n' if the corresponding new value is
null. (In the latter case, the actual value in the corresponding
values entry doesn't matter.) Note that
nulls is not a text string, just an array: it
does not need a '\0' terminator.
new row with modifications, allocated in the upper executor
context, or NULL on error
(see SPI_result for an error indication)
On error, SPI_result is set as follows:
SPI_ERROR_ARGUMENT if rel is NULL, or if
row is NULL, or if ncols
is less than or equal to 0, or if colnum is
NULL, or if values is NULL.
SPI_ERROR_NOATTRIBUTE if colnum contains an invalid column number (less
than or equal to 0 or greater than the number of columns in
row)
SPI_ERROR_UNCONNECTEDif SPI is not active