This is a strange annoying warning that suddenly appeared after I upgraded to JBoss 7.4.2 and was completly flooding my output log. It looks like an warning due to a bad configuration that until version 7.4.2 was ignored. My log looked something like this: Of course the fact that somehow the warning message seems to… Read More »
When trying to add a foreign key to a table sometimes the error ORA-02298 is thrown. Let’s have two tables a MyTable and a MyTableHistory connected by a historyid column from MyTable that points to the id column from MyTableHistory Try then to add add foreign key like: If we are in the case of… Read More »
The ELK (ElasticSearch+LogStash +Kibana ) stack is maybe the best method to monitor your environment in a simple visually applying way. My task was to monitor the parameters of a Jboss/Wildfly application server where my enterprise application is hosted. There are several guides that describe how to deploy the basic stack, I am not going… Read More »
There are instances when one needs to migrate data from a Postgres database to a different PostgreSQL database version or even worse to a restrictive PostgreSQL instance of cloud providers like #AWS-RDS. When migrating to a different version of Postgres after you used to run on a frozen production version for long time it may… Read More »
Sometimes you need to add by hand a primary key on a table that initially did not have any constraint. Most of the time you will run into the issue of having duplicate rows, so first we must make sure there are no duplicate rows. Duplicate rows are the rows that have duplicates in the… Read More »
Starting from openssh 7.8 the default format for private keys has changed from PEM to OpenSSH: That means that private keys generated with the referenced command: (ssh-keygen -t rsa -b 4096) are no longer generated as PEM format. Lot’s of online services do not accept this format yet CircleCI, GitHub are some of the services… Read More »
When you start reading lots of VC tweets and blog posts is easy to get confused by the deluge of acronyms they use. The following are the basic definitions for the most important acronyms. CAC = Customer acquisition cost TAC = Total acquisition cost LTV= Lifetime value TAM = Total available market YoY growth =… Read More »
Systemd doesn’t completely control whether core dumps are made or not. It mainly determine where such dumps go, and whether they should take up space or not. It may prevent some user space core dumps, but not all. With “Storage=none”, they can still occur and are registered by journald, but they don’t take up disk… Read More »
Looking around microservice communication protocols I discovered protocol buffers and gRPC as a new alternative to REST with XML or JSON. XML is used in standards like ISO 20022 for financial messages, JSON is widely used by all the new APIs in fintech (Stripe, TransferWise, lots of PSD2 API implementation of banks etc.) Both of… Read More »
As a new found collector of challenger bank accounts the new #fintech Curve (@imaginecurve) it was an obvious must have. When I heard about this “magic” proxy card, one card to hold all your other cards, I was in awe. How natural and simple idea that fit my case perfectly. Due to the new found… Read More »