> 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/client-interfaces/ecpg/ecpg-oracle-compat.md).

# 34.16. Oracle Compatibility Mode \#

`ecpg` can be run in a so-called *Oracle compatibility mode*. If this mode is active, it tries to behave as if it were Oracle Pro\*C.

Specifically, this mode changes `ecpg` in three ways:

* Pad character arrays receiving character string types with trailing spaces to the specified length
* Zero byte terminate these character arrays, and set the indicator variable if truncation occurs
* Set the null indicator to `-1` when character arrays receive empty character string types

***

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


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