A developer is crucial for managing and analyzing big data effectively. They have expertise in Apache Hive, enabling them to convert complex queries into MapReduce, Apache Tez, or Spark jobs. This simplifies data summarization, querying, and analysis of large data systems. Their proficiency in SQL bridges the gap between the language and Hadoop, making data processing more accessible. They also ensure efficient data warehouse infrastructure, which is useful in handling structured and semi-structured data. Hiring a developer can significantly boost your data processing capabilities, providing valuable insights for your business.