> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/15/server-programming/server-programming-interface/spi-memory/spi-spi-returntuple.md).

# SPI\_returntuple

## SPI\_returntuple

SPI\_returntuple — prepare to return a tuple as a Datum

### Synopsis

```

HeapTupleHeader SPI_returntuple(HeapTuple row, TupleDesc rowdesc)
```

### Description

`SPI_returntuple` makes a copy of a row in the upper executor context, returning it in the form of a row type `Datum`. The returned pointer need only be converted to `Datum` via `PointerGetDatum` before returning.

This function can only be used while connected to SPI. Otherwise, it returns NULL and sets `SPI_result` to `SPI_ERROR_UNCONNECTED`.

Note that this should be used for functions that are declared to return composite types. It is not used for triggers; use `SPI_copytuple` for returning a modified row in a trigger.

### Arguments

`HeapTuple`` `*`row`*

row to be copied

`TupleDesc`` `*`rowdesc`*

descriptor for row (pass the same descriptor each time for most effective caching)

### Return Value

`HeapTupleHeader` pointing to copied row, or `NULL` on error (see `SPI_result` for an error indication)

***

原文：[PostgreSQL 15.19 Documentation](/15/server-programming/server-programming-interface/spi-memory/spi-spi-returntuple.md)（英文原文，待翻譯）


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