Server Programming

This part is about extending the server functionality with user-defined functions, data types, triggers, etc. These are advanced topics which should probably be approached only after all the other user documentation about PostgreSQL has been understood. Later chapters in this part describe the server-side programming languages available in the PostgreSQL distribution as well as general issues concerning server-side programming languages. It is essential to read at least the earlier sections of Chapter 36 (covering functions) before diving into the material about server-side programming languages.

Table of Contents
36. Extending SQL
36.1. How Extensibility Works
36.2. The PostgreSQL Type System
36.3. User-defined Functions
36.4. Query Language ( SQL ) Functions
36.5. Function Overloading
36.6. Function Volatility Categories
36.7. Procedural Language Functions
36.8. Internal Functions
36.9. C-Language Functions
36.10. User-defined Aggregates
36.11. User-defined Types
36.12. User-defined Operators
36.13. Operator Optimization Information
36.14. Interfacing Extensions To Indexes
36.15. Packaging Related Objects into an Extension
36.16. Extension Building Infrastructure
37. Triggers
37.1. Overview of Trigger Behavior
37.2. Visibility of Data Changes
37.3. Writing Trigger Functions in C
37.4. A Complete Trigger Example
38. Event Triggers
38.1. Overview of Event Trigger Behavior
38.2. Event Trigger Firing Matrix
38.3. Writing Event Trigger Functions in C
38.4. A Complete Event Trigger Example
38.5. A Table Rewrite Event Trigger Example
39. The Rule System
39.1. The Query Tree
39.2. Views and the Rule System
39.3. Materialized Views
39.4. Rules on INSERT , UPDATE , and DELETE
39.5. Rules and Privileges
39.6. Rules and Command Status
39.7. Rules Versus Triggers
40. Procedural Languages
40.1. Installing Procedural Languages
41. PL/pgSQL - SQL Procedural Language
41.1. Overview
41.2. Structure of PL/pgSQL
41.3. Declarations
41.4. Expressions
41.5. Basic Statements
41.6. Control Structures
41.7. Cursors
41.8. Errors and Messages
41.9. Trigger Procedures
41.10. PL/pgSQL Under the Hood
41.11. Tips for Developing in PL/pgSQL
41.12. Porting from Oracle PL/SQL
42. PL/Tcl - Tcl Procedural Language
42.1. Overview
42.2. PL/Tcl Functions and Arguments
42.3. Data Values in PL/Tcl
42.4. Global Data in PL/Tcl
42.5. Database Access from PL/Tcl
42.6. Trigger Procedures in PL/Tcl
42.7. Event Trigger Procedures in PL/Tcl
42.8. Error Handling in PL/Tcl
42.9. Modules and the unknown Command
42.10. Tcl Procedure Names
43. PL/Perl - Perl Procedural Language
43.1. PL/Perl Functions and Arguments
43.2. Data Values in PL/Perl
43.3. Built-in Functions
43.4. Global Values in PL/Perl
43.5. Trusted and Untrusted PL/Perl
43.6. PL/Perl Triggers
43.7. PL/Perl Event Triggers
43.8. PL/Perl Under the Hood
44. PL/Python - Python Procedural Language
44.1. Python 2 vs. Python 3
44.2. PL/Python Functions
44.3. Data Values
44.4. Sharing Data
44.5. Anonymous Code Blocks
44.6. Trigger Functions
44.7. Database Access
44.8. Explicit Subtransactions
44.9. Utility Functions
44.10. Environment Variables
45. Server Programming Interface
45.1. Interface Functions
45.2. Interface Support Functions
45.3. Memory Management
45.4. Visibility of Data Changes
45.5. Examples
46. Background Worker Processes
47. Logical Decoding
47.1. Logical Decoding Examples
47.2. Logical Decoding Concepts
47.3. Streaming Replication Protocol Interface
47.4. Logical Decoding SQL Interface
47.5. System Catalogs Related to Logical Decoding
47.6. Logical Decoding Output Plugins
47.7. Logical Decoding Output Writers
47.8. Synchronous Replication Support for Logical Decoding
48. Replication Progress Tracking