All posts by Daniel Westermann
Currently we have many requests to support customers in running PostgreSQL in Docker containers. Some of those use redhat OpenShift as the management platform for their Docker deployments. Setting up an OpenShift cluster requires quite some resources and is nothing you want to do on your workstation usually. To overcome that you can use MiniShift which launches a one node OpenShift cluster which you can use for testing. Setting that up is quite easy.
Puh, that last post in this series is already half a year old. Time is moving too fast Today, while being at a customer again, this question came up: Can I do something comparable in PostgreSQL to what I can do in Oracle, which is: Create a user and provide the hashed password so that the password is the same on the source and the target (which implies not knowing the password at all)? In…
Finally I am home from pgconf.de in Berlin at the beautiful Müggelsee. Beside meeting core PostreSQL people such Devrim and Bruce, Andreas and joining Jan again for great discussions and some beers, joking with Anja, being at the dbi services booth, discussing with people, kidding with Hans: was it worth the effort? Yes, it was, and here is why.
Another partitioning improvement for PostgreSQL 11: Insert…on conflict is now supported (for most cases) in PostgreSQL 11 thanks to this commit. Lets see how it works.
Up to PostgreSQL 10 the wal segment size was fixed once PostgreSQL was compiled and installed. When you wanted to have something else than the default you needed to tell that to the configure command when building from source, e.g. postgres@pgbox:/home/postgres/postgresql/ [PGDEV] ./configure –with-wal-segsize=64MB For PostgreSQL 11 two commits landed (1 and 2) which change this. Lets have a look.
Yes, sounds strange, but exactly this is what we faced today. In the end it is clear and not strange anymore but for a moment we really thought we are hitting a bug in the operating system, which was RedHat 7.4. For the little demo for this post I’ll use CentOS 7.4 but this should not really matter. Lets go.
Every time you send a SQL statement to PostgreSQL it must be parsed. Parsing is fast, yes, but parsing the same statement a thousand times can quickly sum up to quite some time the database could spend for something else. To avoid that PostgreSQL comes with the prepare statement. Using that you can avoid parsing of statements and only planning and executing will happen. Lets see how that works.
In the last post about partitioning improvements in PostgreSQL 11 we talked about unique indexes and primary keys on partitioned tables. Both did not work in PostgreSQL 10 but now do in PostgreSQL 11. Another operation that did not work in PostgreSQL 10 and does now in PostgreSQL 11 is: Updating the partition key, which means that a row will move from one partition to another. Lets have a look at that.
Yesterday, while being at a customer, an interesting question popped up: What is the maximum of in list values in PostgreSQL? I couldn’t answer although I never read somewhere that there is a limit. The following is for fun only and I am not saying that creating huge in lists is a good idea. Lets go.