query

How to Analyze query performance in MongoDB

Reading Time: 2 minutes Analyze query performance in mongodb may became complicated if we do not really know which part should be measured. Fortunately, MongoDB provides very handy tool which can be used to evaluate query performance: explain(“executionStats”). This tool provide us some general measurements such as number of examined document and execution time that can be used to do statistical analysis. The Database and Collection In this easy tutorial, Continue Reading

Spark SQL in Delta Lake 0.7.0

Reading Time: 3 minutes Nowadays Delta lake is a buzz word in the Big Data world, especially among the spark developers because it relegates lots of issues found in the Big Data domain. Delta Lake is an open-source storage layer that brings reliability to data lakes. Delta Lake provides ACID transactions, scalable metadata handling, and unifies streaming and batch data processing. It is evolving day by day and adds cool features in its every release. Continue Reading

Kafka Streams

Interactive Queries in Apache Kafka

Reading Time: 4 minutes Apache Kafka v0.10 introduced a new feature Kafka Streams API Рa client library which can be used for building applications and microservices, where the input and output data can be stored in Kafka clusters. Kafka Streams provides state stores, which can be used by stream processing applications to store and query data.  Every task in Kafka Streams uses one or more state stores which Continue Reading