The article delves into the intricacies of handling case sensitivity in databases, particularly focusing on SQL, JSON, and N1QL. While SQL is generally case insensitive to identifiers and keywords, it remains case sensitive to data, whereas JSON and N1QL are case sensitive to both field names and data. It highlights the challenge of performing case-insensitive queries and suggests using functions to transform data into a uniform case, which facilitates efficient querying through index creation. The discussion extends to complex expressions and array functions, emphasizing the importance of optimizing queries for performance by creating appropriate indexes with the help of tools like Index Advisor. Additionally, it explores the use of Full-Text Search (FTS) for more effective text processing and querying, noting the benefits of custom analyzers to ensure comprehensive case-insensitive searches. The article underscores the significance of verifying query plans to confirm that predicates are properly pushed to index scans, thereby enhancing query performance.