From 2fa255ce9b9536450c9f86bd7c15778f58cf3777 Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Fri, 1 Nov 2024 16:38:16 -0400 Subject: [PATCH] doc: clarify text around MVCC example query Reported-by: marlene.brandstaetter@cargonet.software Discussion: https://postgr.es/m/167765529052.987840.12345375075704447735@wrigleys.postgresql.org Backpatch-through: master --- doc/src/sgml/mvcc.sgml | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/doc/src/sgml/mvcc.sgml b/doc/src/sgml/mvcc.sgml index 380d0c9e805..6c02c226f60 100644 --- a/doc/src/sgml/mvcc.sgml +++ b/doc/src/sgml/mvcc.sgml @@ -417,8 +417,8 @@ does not see effects of those commands on other rows in the database. This behavior makes Read Committed mode unsuitable for commands that involve complex search conditions; however, it is just right for simpler - cases. For example, consider updating bank balances with transactions - like: + cases. For example, consider transferring $100 from one account + to another: BEGIN; @@ -427,8 +427,8 @@ UPDATE accounts SET balance = balance - 100.00 WHERE acctnum = 7534; COMMIT; - If two such transactions concurrently try to change the balance of account - 12345, we clearly want the second transaction to start with the updated + If another transactions concurrently tries to change the balance of account + 7534, we clearly want the second statement to start with the updated version of the account's row. Because each command is affecting only a predetermined row, letting it see the updated version of the row does not create any troublesome inconsistency. -- 2.30.2