Smelly instanceof Operator

The instanceof operator in Java is used to check if a given reference is an instance of (aka object of) a given class. Though it is useful in some situations, it is a bad practice to use the instanceof operator. Whenever I see instanceof in my student's projects or a code review I raise the alarm. This article explains why the instanceof operator is considered a bad practice and how to avoid it.

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Presto SQL: Join Algorithms

Presto is a distributed big data SQL engine initially developed by Facebook and later open-sourced and being led by the community. The last article Presto SQL: Types of Joins covers the fundamentals of join operators available in Presto and how they can be used in SQL queries. With that knowledge, you can now learn the internals of Presto and how it executes join operations internally. This article presents how Presto executes join operations and the algorithms used to join tables.

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Presto SQL: Types of Joins

SQL Join is one of the most important and expensive SQL operation and require deep understanding from database engineers to write efficient SQL queries. From database engineers' perspective, understanding how join operation works help them to optimize them for efficient execution. This article, explains the join operations supported in the open source distributed computing engine: Presto SQL. This article is based on now archived prestodb.rocks blog which I referred to learn the Join algorithms of Presto.

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