Appearance of numerous NoSQL databases on the market results from business requirements of modern information systems that can't be satisfied by traditional relational databases. One of such requirements is an ability to support data which structure is not predefined. PostgreSQL, being a leading relational database, have had support of loosely structured data long before NoSQL had appeared. The feature was reinvigorated by the latest release in a form of the jsonb data type which does not only support the JSON standard, but also possesses a level of performance comparable or even exceeding those of the popular NoSQL databases.<br /> <br /> During a couple of hours we will talk about several types of loosely structured data in PostgreSQL, particularly, about arrays, full text search, hstore (key-value) and jsonb. You will learn about their current functionality, as well as our plans for their improvement.