Part VII. Internals

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

Table of Contents

51. Overview of Postgres Pro Internals
51.1. The Path of a Query
51.2. How Connections Are Established
51.3. The Parser Stage
51.4. The Postgres Pro Rule System
51.5. Planner/Optimizer
51.6. Executor
52. System Catalogs
52.1. Overview
52.2. pg_aggregate
52.3. pg_am
52.4. pg_amop
52.5. pg_amproc
52.6. pg_attrdef
52.7. pg_attribute
52.8. pg_authid
52.9. pg_auth_members
52.10. pg_cast
52.11. pg_class
52.12. pg_collation
52.13. pg_constraint
52.14. pg_conversion
52.15. pg_database
52.16. pg_db_role_setting
52.17. pg_default_acl
52.18. pg_depend
52.19. pg_description
52.20. pg_enum
52.21. pg_event_trigger
52.22. pg_extension
52.23. pg_foreign_data_wrapper
52.24. pg_foreign_server
52.25. pg_foreign_table
52.26. pg_index
52.27. pg_inherits
52.28. pg_init_privs
52.29. pg_language
52.30. pg_largeobject
52.31. pg_largeobject_metadata
52.32. pg_namespace
52.33. pg_opclass
52.34. pg_operator
52.35. pg_opfamily
52.36. pg_parameter_acl
52.37. pg_partitioned_table
52.38. pg_policy
52.39. pg_proc
52.40. pg_profile
52.41. pg_publication
52.42. pg_publication_namespace
52.43. pg_publication_rel
52.44. pg_range
52.45. pg_replication_origin
52.46. pg_rewrite
52.47. pg_role_password
52.48. pg_seclabel
52.49. pg_sequence
52.50. pg_shdepend
52.51. pg_shdescription
52.52. pg_shseclabel
52.53. pg_statistic
52.54. pg_statistic_ext
52.55. pg_statistic_ext_data
52.56. pg_subscription
52.57. pg_subscription_rel
52.58. pg_tablespace
52.59. pg_transform
52.60. pg_trigger
52.61. pg_ts_config
52.62. pg_ts_config_map
52.63. pg_ts_dict
52.64. pg_ts_parser
52.65. pg_ts_template
52.66. pg_type
52.67. pg_user_mapping
53. System Views
53.1. Overview
53.2. pg_available_extensions
53.3. pg_available_extension_versions
53.4. pg_backend_memory_contexts
53.5. pg_config
53.6. pg_cursors
53.7. pg_file_settings
53.8. pg_group
53.9. pg_hba_file_rules
53.10. pg_ident_file_mappings
53.11. pg_indexes
53.12. pg_locks
53.13. pg_matviews
53.14. pg_policies
53.15. pg_prepared_statements
53.16. pg_prepared_xacts
53.17. pg_publication_tables
53.18. pg_replication_origin_status
53.19. pg_replication_slots
53.20. pg_roles
53.21. pg_rules
53.22. pg_seclabels
53.23. pg_sequences
53.24. pg_settings
53.25. pg_shadow
53.26. pg_shmem_allocations
53.27. pg_stats
53.28. pg_stats_ext
53.29. pg_stats_ext_exprs
53.30. pg_tables
53.31. pg_timezone_abbrevs
53.32. pg_timezone_names
53.33. pg_user
53.34. pg_user_mappings
53.35. 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. Custom WAL Resource Managers
64. B-Tree Indexes
64.1. Introduction
64.2. Behavior of B-Tree Operator Classes
64.3. B-Tree Support Functions
64.4. Implementation
65. GiST Indexes
65.1. Introduction
65.2. Built-in Operator Classes
65.3. Extensibility
65.4. Implementation
65.5. Examples
66. SP-GiST Indexes
66.1. Introduction
66.2. Built-in Operator Classes
66.3. Extensibility
66.4. Implementation
67. GIN Indexes
67.1. Introduction
67.2. Built-in Operator Classes
67.3. Extensibility
67.4. Implementation
67.5. GIN Tips and Tricks
67.6. Limitations
67.7. Examples
68. BRIN Indexes
68.1. Introduction
68.2. Built-in Operator Classes
68.3. Extensibility
69. Hash Indexes
69.1. Overview
69.2. Implementation
70. Database Physical Storage
70.1. Database File Layout
70.2. TOAST
70.3. Free Space Map
70.4. Visibility Map
70.5. The Initialization Fork
70.6. Database Page Layout
70.7. Heap-Only Tuples (HOT)
71. How the Planner Uses Statistics
71.1. Row Estimation Examples
71.2. Multivariate Statistics Examples
71.3. Planner Statistics and Security
72. Backup Manifest Format
72.1. Backup Manifest Top-level Object
72.2. Backup Manifest File Object
72.3. Backup Manifest WAL Range Object