742bd91a83
_bt_first reliably uses the same equality key (on each index column) for initial positioning purposes as the one that _bt_checkkeys can use to end the scan following commitf09816a0. _bt_first no longer applies its own independent rules to determine which initial positioning key to use on each column (for equality and inequality keys alike). Preprocessing is now fully in control of determining which keys start and end each scan, ensuring that _bt_first and _bt_checkkeys have symmetric behavior. Remove obsolete comments that described why _bt_first was expected to use at least one of the available required equality keys for initial positioning purposes. The rules in this area are now maximally strict and uniform, so there's no reason to draw attention to equality keys. Any column with a required equality key cannot have a redundant required inequality key (nor can it have a redundant required equality key). Oversight in commitf09816a0, which removed similar comments from _bt_first, but missed these comments. Author: Peter Geoghegan <pg@bowt.ie> Backpatch-through: 18
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
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