From c08b3e9413b745b005c67b5333569055066a6a9e Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Wed, 22 Jun 2022 14:33:26 -0400 Subject: [PATCH] doc: clarify wording about phantom reads Reported-by: akhilhello@gmail.com Discussion: https://postgr.es/m/165222922369.669.10475917322916060899@wrigleys.postgresql.org Backpatch-through: 10 --- doc/src/sgml/high-availability.sgml | 2 +- doc/src/sgml/mvcc.sgml | 7 ++++--- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml index 69e57c68b3a..72b50bae79f 100644 --- a/doc/src/sgml/high-availability.sgml +++ b/doc/src/sgml/high-availability.sgml @@ -2334,7 +2334,7 @@ LOG: database system is ready to accept read only connections Currently, temporary table creation is not allowed during read only transactions, so in some cases existing scripts will not run correctly. This restriction might be relaxed in a later release. This is - both a SQL Standard compliance issue and a technical issue. + both a SQL standard compliance issue and a technical issue. diff --git a/doc/src/sgml/mvcc.sgml b/doc/src/sgml/mvcc.sgml index d51641079a0..75df5e4947c 100644 --- a/doc/src/sgml/mvcc.sgml +++ b/doc/src/sgml/mvcc.sgml @@ -277,9 +277,10 @@ The table also shows that PostgreSQL's Repeatable Read implementation - does not allow phantom reads. Stricter behavior is permitted by the - SQL standard: the four isolation levels only define which phenomena - must not happen, not which phenomena must happen. + does not allow phantom reads. This is acceptable under the SQL + standard because the standard specifies which anomalies must + not occur at certain isolation levels; higher + guarantees are acceptable. The behavior of the available isolation levels is detailed in the following subsections. -- 2.39.5