Book Image

PostgreSQL 11 Administration Cookbook

By : Simon Riggs, Gianni Ciolli, Sudheer Kumar Meesala
Book Image

PostgreSQL 11 Administration Cookbook

By: Simon Riggs, Gianni Ciolli, Sudheer Kumar Meesala

Overview of this book

PostgreSQL is a powerful, open source database management system with an enviable reputation for high performance and stability. With many new features in its arsenal, PostgreSQL 11 allows you to scale up your PostgreSQL infrastructure. This book takes a step-by-step, recipe-based approach to effective PostgreSQL administration. The book will introduce you to new features such as logical replication, native table partitioning, additional query parallelism, and much more to help you to understand and control, crash recovery and plan backups. You will learn how to tackle a variety of problems and pain points for any database administrator such as creating tables, managing views, improving performance, and securing your database. As you make steady progress, the book will draw attention to important topics such as monitoring roles, backup, and recovery of your PostgreSQL 11 database to help you understand roles and produce a summary of log files, ensuring high availability, concurrency, and replication. By the end of this book, you will have the necessary knowledge to manage your PostgreSQL 11 database efficiently.
Table of Contents (19 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Granting user access to specific rows


PostgreSQL supports granting users privileges on some rows only.

 

Getting ready

This recipe uses RLS, which is available only in PostgreSQL version 9.5 or later, so start by checking that you are not using an older version.

As for the previous recipe, we assume that there is already a schema called someschema and a role called somerole with USAGE privileges on it. We create a new table to experiment with row-level privileges:

CREATE TABLE someschema.sometable3(col1 int, col2 text);

RLS must also be enabled on that table:

ALTER TABLE someschema.sometable3 ENABLE ROW LEVEL SECURITY;

How to do it…

First, we grant somerole the privilege to view the contents of the table, as we did in the previous recipe:

GRANT SELECT ON someschema.sometable3 TO somerole;

Let's assume that the contents of the table are as shown by the following command:

SELECT * FROM someschema.sometable3;
 col1 |   col2   
------+-----------
    1 | One
   -1 | Minus one
(2 rows)

In order to grant the...