Hazelcast IMDG Standard Support has expired. Extended support for version 4.1 ends in April 2024. Extended support for version 4.2 ends in September 2024.

We recommend that you try Hazelcast Platform.

In Hazelcast Platform, we’ve combined the in-memory storage of IMDG with the stream processing power of Jet. Find out more in our Platform documentation.

The following topics are a good place to start:


The SQL service provided by Hazelcast allows you to query data stored in IMap declaratively.

The SQL feature is currently in beta. The compatibility between versions is not guaranteed. API might change between versions without notice.
If you’re using the hazelcast-all or hazelcast-enterprise-all packages, the hazelcast-sql module is included in them by default. If not, i.e., you are using hazelcast or hazelcast-enterprise, then you need to have hazelcast-sql in the classpath.

Example: How to Query an IMap using SQL

Consider that we have a map called emp that contains values of type Employee:

public class Employee implements Serializable {
    private String name;
    private int age;

    public Employee(String name, int age) {
        this.name = name;
        this.age = age;

    public String getName() {
        return name;

    public int getAge() {
        return age;

The following code prints names of the employees whose age is less than 30:

try (SqlResult result = hazelcastInstance.getSql().execute("SELECT name FROM emp WHERE age < ?", 30)) {
    for (SqlRow row : result) {
        String name = row.getObject(0);


You can run the same code snippet from a member or a client.