Some co-workers started using Apache Kafka con a bunch of our Customers.

Apache Kafka is a community distributed event streaming platform capable of handling trillions of events a day. Initially conceived as a messaging queue, Kafka is based on an abstraction of a distributed commit log[*].

To get this goal, Apache Kafka needs a complex servers setup, even more complex if you want the certification for the producing company (Confluent).  Now, if you are planning to use Kafka like a simple JavaMessaeSystem (JMS) implementation, think twice before going on this route.

PostgreSQL 12 offers a fair (and open source) partition implementation, whereas if money are not a problem, Oracle 12c can happy scale on billions of record before running into troubles (and ExaData can scale even more).

PostgreSQL and Oracle offer optimizations for partitioned data, called “Partition Pruning” in PostreSQL teminology:

With partition pruning enabled, the planner will examine the definition of each partition and prove that the partition need not be scanned because it could not contain any rows meeting the query's WHERE clause. When the planner can prove this, it excludes (prunes) the partition from the query plan.

This feature is quite brand new (popped in PostreSQL 11) but it is essential to a successful partition strategy. Before these feature, partitioning was a black magic art. Now it is simpler to manage.
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Use docker in docker to drive docker from a container Working under windows, sometimes docker slow down. Sometimes you need to access to the MobyVM. With this line:

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Ring - Cache interface as a programming language integrationRing provides function-oriented cache interface for various backends.

Repository:

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isync: free IMAP and MailDir mailbox synchronizerisync is a command line application which synchronizes mailboxes; currently Maildir and IMAP4 mailboxes are supported. New messages, message deletions and flag changes can be propagated both ways. isync is suitable for use in IMAP-disconnected mode.Synchronization is based on unique message identifiers (UIDs), so no identification conflicts can occur (as opposed to some other mail synchronizers).Synchronization state is kept in one local text file per mailbox pair; multiple replicas of a mailbox can be maintained.isync is free software in the sense of the GNU GPL v2.

Source: isync: free IMAP and MailDir mailbox synchronizer

On these days I decided to tune a bit more, my new shiny linux server box. I started to set up fail2ban. I think fail2ban is very imporant nowadays because it is a good example of a tool for slowing down attacks without closing your server too much.

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To understand Angular 4, after the “Hero” tutorial you should start from the Template syntax. 

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Ci sono una nuova generazione di “nullasapienti”, persone che con una inutile laurea (tipicamente in legge) diventano giornalisti dilettanti, seguono i trend della “blogosfera” e leggono magari qualche bel libro di comunicazione.

Il risultato è che pubblicano video che non sono scontati, non sono banali ma non sono neppure perle di saggezza. Sono ovvi. La cosa diventa meno bella se mettendoci la loro faccia, vogliono pure dei soldi da voi.

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Arduino is a great hardware for a lot of reason: easy to use, difficulto to break, it is a very solid 5-Volt board.

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Sometimes you need to remove nasty duplicate on a table, based on a subset of the column. On every big database there is something called “rowid” which can be used to indentify a column in a unique way. On PostgreSQL is called ctid, as we shall see:

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In Excel you can easily fill in a column with a list of values. Some times also in Emacs you my need to write down a bunch of similar code. The dotimes function with the “elsp eval” M-x : (Esc + : on windooze) will solve your trouble easily. Try out this code on scratch buffer:

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