SPI_MODIFYTUPLE(3)

🌸 NAME 🌸

okay so welcome to the SPI_MODIFYTUPLE(3) page from the PostgreSQL 14.24 documentation, bestie. SPI_modifytuple — create a row by replacing selected fields of a given row. That's the whole vibe in one line, and honestly? iconic. 💅

✨ SYNOPSIS ✨

HeapTuple SPI_modifytuple(Relation rel, HeapTuple row, int ncols,
                          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. 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. So like, if SPI isn't active, it's not giving new-row energy. 😭

🎀 ARGUMENTS 🎀

• 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.) They said it, not me, but we respect the lore.
• 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.

👑 RETURN VALUE 👑

You get a new row with modifications, allocated in the upper executor context, or NULL on error (see SPI_result for an error indication). Slay when it works, check the error when it doesn't. 💖

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.

mwah 💋 — this whole page is PostgreSQL 14.24, dated 2026, and it's a SPI_MODIFYTUPLE(3) moment fr fr. 🌈✨