The First Cry of Atom

In Java, toString() method is useful for debugging. It can print the object information in human readable format. Member variables and state can be returned. Only painful stuff of toString() is that we need to implement by ourselves for custom class. [Read More]

Presto is a fast distributed SQL engine originally developed by Facebook. From 0.153, pluggable resource group was introduced. This feature enables us to separate cluster resource in account workload. For example, you want to ensure daily batch job resource allocation even if you submit some adhoc queries. In short when... [Read More]

We often want to exclude some test cases. ScalaTest has @Ignore annotation to exclude that test case to be run as well as JUnit. But how can we include or exclude test cases in more fine-grained way? [Read More]

2回目はIn-Memory Databaseに関する講義。第1回目に関してはここで書いた。 [Read More]

Historically, there are a lot of researches about data structure and algorithms. This is a core field of computer science from the past. I’m especially interested in hash table among them because it is simple data structure and widely used but there are a lot of inspiring ideas in hash... [Read More]