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8. DataQL engine

The DataQL engine compiles scripts into QIL and executes them directly in Java applications. Create queries through HostConfiguration → QueryManager → QueryBuilder → Query and supply parameters at execution time.

Compilation and execution​

The parser creates a query model, which the compiler turns into QIL. The executor runs the instructions, invokes UDFs as needed and returns the query result.

DataQL compilation and execution

Add the dependency​

pom.xml
<dependency>
    <groupId>net.hasor</groupId>
    <artifactId>dataql-engine</artifactId>
    <version>5.0.0</version>
</dependency>

Run your first query​

QueryExample.java
import java.util.Map;
import net.hasor.dataql.host.HostConfiguration;
import net.hasor.dataql.host.Query;
import net.hasor.dataql.host.QueryManager;
import net.hasor.dataql.kernel.QueryResult;

public class QueryExample {
    public static void main(String[] args) throws Exception {
        HostConfiguration host = new HostConfiguration();
        QueryManager manager = new QueryManager(host);
        Query query = manager.newBuilder().createQuery("return ${name};");
        QueryResult result = query.execute(Map.of("name", "DataQL"));
        System.out.println(result.getData().unwrap());
    }
}

The script reads the supplied parameter through ${name}. result.getData().unwrap() converts the result into a Java object. Running the example prints:

DataQL

Guides​

  • Standalone usage: Supply parameters, reuse compiled code and handle results.
  • Data models: Convert Java data, read results and handle binary resources.
  • Core APIs: Understand configuration, builders, queries and result objects.
  • SQL executor: Add SQL execution and configure database connections.
  • JSR-223: Execute and precompile queries through the JDK scripting APIs.
  • QIL instruction reference: Look up instructions when inspecting compiled code.

For functions, fragments, Finders and scopes, see Engine extensions.