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_aios
53.3. pg_available_extensions
53.4. pg_available_extension_versions
53.5. pg_backend_memory_contexts
53.6. pg_config
53.7. pg_cursors
53.8. pg_file_settings
53.9. pg_group
53.10. pg_hba_file_rules
53.11. pg_ident_file_mappings
53.12. pg_indexes
53.13. pg_locks
53.14. pg_matviews
53.15. pg_policies
53.16. pg_prepared_statements
53.17. pg_prepared_xacts
53.18. pg_publication_tables
53.19. pg_replication_origin_status
53.20. pg_replication_slots
53.21. pg_roles
53.22. pg_rules
53.23. pg_seclabels
53.24. pg_sequences
53.25. pg_settings
53.26. pg_shadow
53.27. pg_shmem_allocations
53.28. pg_shmem_allocations_numa
53.29. pg_stats
53.30. pg_stats_ext
53.31. pg_stats_ext_exprs
53.32. pg_stats_vacuum_database
53.33. pg_stats_vacuum_indexes
53.34. pg_stats_vacuum_tables
53.35. pg_tables
53.36. pg_timezone_abbrevs
53.37. pg_timezone_names
53.38. pg_user
53.39. pg_user_mappings
53.40. pg_views
53.41. pg_wait_events
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. Write Ahead Logging for Extensions
62.1. Generic WAL Records
62.2. Custom WAL Resource Managers
63. Built-in Index Access Methods
63.1. B-Tree Indexes
63.2. GiST Indexes
63.3. SP-GiST Indexes
63.4. GIN Indexes
63.5. BRIN Indexes
63.6. Hash Indexes
64. Database Physical Storage
64.1. Database File Layout
64.2. TOAST
64.3. Free Space Map
64.4. Visibility Map
64.5. The Initialization Fork
64.6. Database Page Layout
64.7. Heap-Only Tuples (HOT)
65. Transaction Processing
65.1. Transactions and Identifiers
65.2. Transactions and Locking
65.3. Subtransactions
65.4. Two-Phase Transactions
66. How the Planner Uses Statistics
66.1. Row Estimation Examples
66.2. Multivariate Statistics Examples
66.3. Planner Statistics and Security
67. Backup Manifest Format
67.1. Backup Manifest Top-level Object
67.2. Backup Manifest File Object
67.3. Backup Manifest WAL Range Object