This is the third and last part of blog articles dedicated to pg_rewind. In the two previous articles we have seen how pg_rewind is useful to fix split-brain events due to mistakes in the switchover procedures, avoiding the need of new base backups. We have also seen that this is true for simple replication clusters, where more standby nodes are involved.
In the previous blog article we have seen how pg_rewind works with a simple HA cluster, composed of a master node replicating to a standby. In this context, an eventual switchover involves just two nodes that have to be aligned. But what happens with HA clusters when there are several (also cascading) standbys? Now, consider […]
Since PostgreSQL 9.5, pg_rewind has been able to make a former master follow up a promoted standby although, in the meantime, it proceeded with its own timeline. Consider, for instance, the case of a switchover that didn’t work properly. Have you ever experienced a “split brain” during a switchover operation? You know, when the goal […]
Last week I was pleased to attend Code Sprint 2016 in Paris, organised by the OSGeo Foundation: it has been an opportunity for many GIS users from all over the world to get together, discuss and actively work on many open tasks of some of the major open source frameworks on GIS. PostGIS was obviously […]
PostgreSQL 9.4 extends the SQL standard by inserting two new clauses that facilitate many operations required during the development of applications: the WITHIN GROUP and FILTER clauses.
The introduction of the JSONB data type in PostgreSQL, definitely makes the “NoSQL” side of this relational DBMS come out: this introduction meets the requirements of all those who prefer a data structure in a “key-value” array, dictionary style (widely used in the field of development) and, at the same time, ensures all the advantages […]
Written by Giuseppe Broccolo Since PostgreSQL 9.3, it is possible to update and insert into views directly, so long as the view refers to only one underlying table. PostgreSQL 9.4 allows us to use the CHECK clause for INSERTs into updatable views. For example, consider a table composed of just one integer column; and […]