FIR-26385 send additional parameters to real engine only

src/integrationTest/java/integration/tests/ConnectionTest.java

@@ -0,0 +1,31 @@
+package integration.tests;
+
+import integration.ConnectionInfo;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInstance;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+import static java.lang.String.format;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
+public class ConnectionTest {
+    /**
+     * This test connects to specific engine with additional property {@code use_standard_sql} supported by user engine but
+     * not supported by system engine used here to retrieve the data of user engine.
+     * The test is needed because there were create connection to system engine by copying all given connection properties
+     * while additional (custom) parameters should be ignored.
+     * @throws SQLException if something went wrong
+     */
+    @Test
+    void connectionWithAdditionalProperties() throws SQLException {
+        ConnectionInfo params = integration.ConnectionInfo.getInstance();
+        String url = format("jdbc:firebolt:%s?env=%s&engine=%s&account=%s&use_standard_sql=1", params.getDatabase(), params.getEnv(), params.getEngine(), params.getAccount());
+        try(Connection connection = DriverManager.getConnection(url, params.getPrincipal(), params.getSecret())) {
+            assertNotNull(connection);
+        }
+    }
+}

src/main/java/com/firebolt/jdbc/connection/FireboltConnection.java

@@ -182,6 +182,7 @@ private FireboltProperties createInternalSystemEngineProperties(String accessTok
 		return this.loginProperties
 				.toBuilder()
 				.systemEngine(true)
+				.additionalProperties(Map.of())
 				.compress(false)
 				.host(UrlUtil.createUrl(systemEngineEndpoint).getHost()).database(null).build();
 	}