> 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/server-programming/spi/spi-interface/spi-spi-getargtypeid.md).

# SPI\_getargtypeid

### SPI\_getargtypeid

SPI\_getargtypeid — return the data type OID for an argument of a statement prepared by `SPI_prepare`

### Synopsis

```

Oid SPI_getargtypeid(SPIPlanPtr plan, int argIndex)
```

### Description

`SPI_getargtypeid` returns the OID representing the type for the *`argIndex`*'th argument of a statement prepared by `SPI_prepare`. First argument is at index zero.

### Arguments

`SPIPlanPtr plan` : prepared statement (returned by `SPI_prepare`)

`int argIndex` : zero based index of the argument

### Return Value

The type OID of the argument at the given index. If the *`plan`* is `NULL` or invalid, or *`argIndex`* is less than 0 or not less than the number of arguments declared for the *`plan`*, `SPI_result` is set to `SPI_ERROR_ARGUMENT` and `InvalidOid` is returned.

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/spi-spi-getargtypeid.html)（英文原文，待翻譯）


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