In this chapter, you learned some advanced techniques to query a Neo4j database. First of all, we used the WHERE statement to filter data. Text values can be filtered using regular expressions, which are very flexible and powerful tools to work with strings. Numbers can be filtered using mathematical operators and functions. Logical expressions can be built using Boolean operators (OR, AND, XOR, and NOT). Collections can be filtered using collection predicates.

Paging data is an important feature for a database, especially when it can be very large. You learned how to page data using the LIMIT and SKIP keywords. An important part of this chapter is about aggregating. You learned how to use the RETURN clause to aggregate data with the most common aggregation functions, especially COUNT, SUM, AVG, MAX, and MIN. Finally, we took a look at two useful features of this language: the WITH and UNION keywords. The WITH keyword is used to split queries in order to make them easier to write. The UNION keyword is used to merge two or more result sets.

In the next chapter, you will learn how to create a database using Cypher writing clauses.