> 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/pltcl.md).

# Chapter 42. PL/Tcl — Tcl Procedural Language

**Table of Contents**

[42.1. Overview](/server-programming/pltcl/pltcl-overview.md)

[42.2. PL/Tcl Functions and Arguments](/server-programming/pltcl/pltcl-functions.md)

[42.3. Data Values in PL/Tcl](/server-programming/pltcl/pltcl-data.md)

[42.4. Global Data in PL/Tcl](/server-programming/pltcl/pltcl-global.md)

[42.5. Database Access from PL/Tcl](/server-programming/pltcl/pltcl-dbaccess.md)

[42.6. Trigger Functions in PL/Tcl](/server-programming/pltcl/pltcl-trigger.md)

[42.7. Event Trigger Functions in PL/Tcl](/server-programming/pltcl/pltcl-event-trigger.md)

[42.8. Error Handling in PL/Tcl](/server-programming/pltcl/pltcl-error-handling.md)

[42.9. Explicit Subtransactions in PL/Tcl](/server-programming/pltcl/pltcl-subtransactions.md)

[42.10. Transaction Management](/server-programming/pltcl/pltcl-transactions.md)

[42.11. PL/Tcl Configuration](/server-programming/pltcl/pltcl-config.md)

[42.12. Tcl Procedure Names](/server-programming/pltcl/pltcl-procnames.md)

PL/Tcl is a loadable procedural language for the PostgreSQL database system that enables the [Tcl language](https://www.tcl.tk/) to be used to write PostgreSQL functions and procedures.

***

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


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