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 rel
Used only as the source of the row descriptor for the row. (Passing a relation rather than a row descriptor is a misfeature.)
HeapTuple row
row to be modified
int ncols
number 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_UNCONNECTED
if SPI is not active