Skip to Content
PostgreSQL 10 Administration Cookbook - Fourth Edition
book

PostgreSQL 10 Administration Cookbook - Fourth Edition

by Simon Riggs, Gianni Ciolli
May 2018
Intermediate to advanced content levelIntermediate to advanced
576 pages
30h 25m
English
Packt Publishing
Content preview from PostgreSQL 10 Administration Cookbook - Fourth Edition

How to do it…

Rewrite your application so that the SQL is transformed into two separate transactions, with a double-check to ensure that the rows haven't changed (pay attention to the placeholders):

SELECT A.*, (A.*::text) AS old_acc_infoFROM accounts a WHERE holder_name ='BOB';<do some calculations here>UPDATE accounts SET balance = 42.00WHERE holder_name ='BOB'AND (A.*::text) = <old_acc_info from select above>;

Then, check whether the UPDATE operation really did update one row in your application code. If it did not, then the account for BOB was modified between SELECT and UPDATE, and you probably need to rerun your entire operation (both transactions).

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

PostgreSQL 13 Cookbook

PostgreSQL 13 Cookbook

Vallarapu Naga Avinash Kumar
PostgreSQL 9 Administration Cookbook - Second Edition

PostgreSQL 9 Administration Cookbook - Second Edition

Simon Riggs, GIANNI CIOLLI, Hannu Krosing, Gabriele Bartolini

Publisher Resources

ISBN: 9781788474924Supplemental Content