Which of the following is NOT a characteristic of a relational database?

A relational database is defined by its fundamental characteristics, which include the organization of data in tables, the use of foreign keys to establish relationships between those tables, and the ability to manipulate and query data using Structured Query Language (SQL).

The organization of data in tables is a core aspect of relational databases. Each table consists of rows and columns, where each row represents a record and each column represents a field within the record. This tabular structure simplifies data management and retrieval.

Relationships among data in relational databases are indeed established through foreign keys. A foreign key is a field (or a collection of fields) in one table that uniquely identifies a row of another table, allowing for relationships and joins to exist between different sets of data.

Data manipulation using SQL is another defining feature of relational databases. SQL (Structured Query Language) is a standardized language used for managing and manipulating relational databases. It allows users to create, read, update, and delete data easily.

On the other hand, stating that "Data cannot be easily queried" is contrary to the nature of relational databases. In fact, one of the main advantages of using a relational database is the ability to query data efficiently and straightforwardly through SQL, making complex data retrieval easy for users. Therefore,