> 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/11/appendixes/h.-wai-bu-zhuan-an/h.3.-procedural-languages.md).

# H.3. Procedural Languages

PostgreSQL includes several procedural languages with the base distribution: [PL/pgSQL](https://www.postgresql.org/docs/10/static/plpgsql.html), [PL/Tcl](https://www.postgresql.org/docs/10/static/pltcl.html), [PL/Perl](https://www.postgresql.org/docs/10/static/plperl.html), and [PL/Python](https://www.postgresql.org/docs/10/static/plpython.html).

In addition, there are a number of procedural languages that are developed and maintained outside the core PostgreSQL distribution. [Table H.2](https://www.postgresql.org/docs/10/static/external-pl.html#PL-LANGUAGE-TABLE) lists some of these packages. Note that some of these projects might not be released under the same license as PostgreSQL. For more information on each procedural language, including licensing information, refer to its website and documentation.

**Table H.2. Externally Maintained Procedural Languages**

| Name    | Language   | Website                             |
| ------- | ---------- | ----------------------------------- |
| PL/Java | Java       | <https://tada.github.io/pljava/>    |
| PL/Lua  | Lua        | <https://github.com/pllua/pllua>    |
| PL/R    | R          | <http://www.joeconway.com/plr.html> |
| PL/sh   | Unix shell | <https://github.com/petere/plsh>    |
| PL/v8   | JavaScript | <https://github.com/plv8/plv8>      |


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