SPI_modifytuple
Synopsis
HeapTuple SPI_modifytuple(Relationrel, HeapTuplerow, intncols, int *colnum, Datum *values, const char *nulls)
Description
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.
Arguments
- Relationrel
Used only as the source of the row descriptor for the row. (Passing a relation rather than a row descriptor is a misfeature.)
- HeapTuplerow
row to be modified
- intncols
number of columns to be changed
- int *colnum
an array of lengthncols, containing the numbers of the columns that are to be changed (column numbers start at 1)
- Datum *values
an array of lengthncols, containing the new values for the specified columns
- const char *nulls
an array of lengthncols, describing which new values are null
Ifnulls isNULL then
SPI_modifytupleassumes that no new values are null. Otherwise, each entry of thenulls 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 correspondingvalues entry doesn't matter.) Note thatnulls is not a text string, just an array: it does not need a'\0' terminator.
Return Value
new row with modifications, allocated in the upper executor context;NULL only ifrow isNULL
On error,SPI_result is set as follows:
- SPI_ERROR_ARGUMENT
ifrel isNULL, or ifrow isNULL, or ifncols is less than or equal to 0, or ifcolnum isNULL, or ifvalues isNULL.
- SPI_ERROR_NOATTRIBUTE
ifcolnum contains an invalid column number (less than or equal to 0 or greater than the number of column inrow)