Part VII. Internals

This part contains assorted information that might be of use to Postgres Pro developers.

Table of Contents

52. Overview of Postgres Pro Internals
52.1. The Path of a Query
52.2. How Connections Are Established
52.3. The Parser Stage
52.4. The Postgres Pro Rule System
52.5. Planner/Optimizer
52.6. Executor
53. System Catalogs
53.1. Overview
53.2. pg_aggregate
53.3. pg_am
53.4. pg_amop
53.5. pg_amproc
53.6. pg_attrdef
53.7. pg_attribute
53.8. pg_authid
53.9. pg_auth_members
53.10. pg_cast
53.11. pg_class
53.12. pg_collation
53.13. pg_constraint
53.14. pg_conversion
53.15. pg_database
53.16. pg_db_role_setting
53.17. pg_default_acl
53.18. pg_depend
53.19. pg_description
53.20. pg_enum
53.21. pg_event_trigger
53.22. pg_extension
53.23. pg_foreign_data_wrapper
53.24. pg_foreign_server
53.25. pg_foreign_table
53.26. pg_index
53.27. pg_inherits
53.28. pg_init_privs
53.29. pg_language
53.30. pg_largeobject
53.31. pg_largeobject_metadata
53.32. pg_namespace
53.33. pg_opclass
53.34. pg_operator
53.35. pg_opfamily
53.36. pg_partitioned_table
53.37. pg_pltemplate
53.38. pg_policy
53.39. pg_proc
53.40. pg_publication
53.41. pg_publication_rel
53.42. pg_range
53.43. pg_replication_origin
53.44. pg_rewrite
53.45. pg_seclabel
53.46. pg_sequence
53.47. pg_shdepend
53.48. pg_shdescription
53.49. pg_shseclabel
53.50. pg_statistic
53.51. pg_statistic_ext
53.52. pg_statistic_ext_data
53.53. pg_subscription
53.54. pg_subscription_rel
53.55. pg_tablespace
53.56. pg_transform
53.57. pg_trigger
53.58. pg_ts_config
53.59. pg_ts_config_map
53.60. pg_ts_dict
53.61. pg_ts_parser
53.62. pg_ts_template
53.63. pg_type
53.64. pg_user_mapping
53.65. System Views
53.66. pg_available_extensions
53.67. pg_available_extension_versions
53.68. pg_config
53.69. pg_cursors
53.70. pg_file_settings
53.71. pg_group
53.72. pg_hba_file_rules
53.73. pg_indexes
53.74. pg_locks
53.75. pg_matviews
53.76. pg_policies
53.77. pg_prepared_statements
53.78. pg_autoprepared_statements
53.79. pg_prepared_xacts
53.80. pg_publication_tables
53.81. pg_replication_origin_status
53.82. pg_replication_slots
53.83. pg_roles
53.84. pg_rules
53.85. pg_seclabels
53.86. pg_sequences
53.87. pg_settings
53.88. pg_shadow
53.89. pg_stats
53.90. pg_stats_ext
53.91. pg_tables
53.92. pg_timezone_abbrevs
53.93. pg_timezone_names
53.94. pg_user
53.95. pg_user_mappings
53.96. pg_views
54. Frontend/Backend Protocol
54.1. Overview
54.2. Message Flow
54.3. SASL Authentication
54.4. Streaming Replication Protocol
54.5. Logical Streaming Replication Protocol
54.6. Message Data Types
54.7. Message Formats
54.8. Error and Notice Message Fields
54.9. Logical Replication Message Formats
54.10. Summary of Changes since Protocol 2.0
55. Writing a Procedural Language Handler
56. Writing a Foreign Data Wrapper
56.1. Foreign Data Wrapper Functions
56.2. Foreign Data Wrapper Callback Routines
56.3. Foreign Data Wrapper Helper Functions
56.4. Foreign Data Wrapper Query Planning
56.5. Row Locking in Foreign Data Wrappers
57. Writing a Table Sampling Method
57.1. Sampling Method Support Functions
58. Writing a Custom Scan Provider
58.1. Creating Custom Scan Paths
58.2. Creating Custom Scan Plans
58.3. Executing Custom Scans
59. Genetic Query Optimizer
59.1. Query Handling as a Complex Optimization Problem
59.2. Genetic Algorithms
59.3. Genetic Query Optimization (GEQO) in Postgres Pro
59.4. Further Reading
60. Table Access Method Interface Definition
61. Index Access Method Interface Definition
61.1. Basic API Structure for Indexes
61.2. Index Access Method Functions
61.3. Index Scanning
61.4. Index Locking Considerations
61.5. Index Uniqueness Checks
61.6. Index Cost Estimation Functions
62. Generic WAL Records
63. B-Tree Indexes
63.1. Introduction
63.2. Behavior of B-Tree Operator Classes
63.3. B-Tree Support Functions
63.4. Implementation
64. GiST Indexes
64.1. Introduction
64.2. Built-in Operator Classes
64.3. Extensibility
64.4. Implementation
64.5. Examples
65. SP-GiST Indexes
65.1. Introduction
65.2. Built-in Operator Classes
65.3. Extensibility
65.4. Implementation
66. GIN Indexes
66.1. Introduction
66.2. Built-in Operator Classes
66.3. Extensibility
66.4. Implementation
66.5. GIN Tips and Tricks
66.6. Limitations
66.7. Examples
67. BRIN Indexes
67.1. Introduction
67.2. Built-in Operator Classes
67.3. Extensibility
68. Hash Indexes
68.1. Overview
68.2. Implementation
69. Database Physical Storage
69.1. Database File Layout
69.2. TOAST
69.3. Free Space Map
69.4. Visibility Map
69.5. The Initialization Fork
69.6. Database Page Layout
69.7. Heap-Only Tuples (HOT)
70. How the Planner Uses Statistics
70.1. Row Estimation Examples
70.2. Multivariate Statistics Examples
70.3. Planner Statistics and Security