[jdbc-v2] Fix kill query with active session

jdbc-v2/src/main/java/com/clickhouse/jdbc/StatementImpl.java

@@ -333,9 +333,21 @@ public void cancel() throws SQLException {
             return;
         }
 
-        try (QueryResponse response = connection.getClient().query(String.format("KILL QUERY%sWHERE query_id = '%s'",
-                connection.onCluster ? " ON CLUSTER " + connection.cluster + " " : " ",
-                lastQueryId), connection.getDefaultQuerySettings()).get()){
+        final String sql = "KILL QUERY "
+            + (connection.onCluster ? "ON CLUSTER " + connection.cluster + " " : "")
+            + "WHERE query_id = '" + lastQueryId + "'";
+
+        // Create query settings without session to avoid "Session is locked by a concurrent client" error
+        // We copy default connection settings but explicitly clear session-related settings
+        QuerySettings killQuerySettings = new QuerySettings();
+        if (connection.getDefaultQuerySettings() != null) {
+            killQuerySettings.getAllSettings().putAll(connection.getDefaultQuerySettings().getAllSettings());
+        }
+        // Clear session settings to prevent KILL QUERY from using the locked session
+        killQuerySettings.setSessionId(null);
+        killQuerySettings.setSessionCheck(false);
+
+        try (QueryResponse response = connection.getClient().query(sql, killQuerySettings).get()){
             LOG.debug("Query {} was killed by {}", lastQueryId, response.getQueryId());
         } catch (Exception e) {
             throw new SQLException(e);

jdbc-v2/src/test/java/com/clickhouse/jdbc/StatementTest.java

@@ -611,6 +611,51 @@ public void testConcurrentCancel() throws Exception {
         }
     }
 
+    @Test(groups = {"integration"})
+    public void testCancelWithSessionId() throws Exception {
+        // Test for issue #2690 - Cancel statement should work with active session
+        String sessionId = java.util.UUID.randomUUID().toString();
+        Properties props = new Properties();
+        props.put("clickhouse_setting_session_id", sessionId);
+
+        try (Connection conn = getJdbcConnection(props);
+             StatementImpl stmt = (StatementImpl) conn.createStatement()) {
+
+            // Verify session is applied from connection settings by checking system.query_log
+            stmt.executeQuery("SELECT 1").close();
+            String queryId = stmt.getLastQueryId();
+            stmt.execute("SYSTEM FLUSH LOGS");
+
+            try (ResultSet rs = stmt.executeQuery("SELECT session_id FROM system.query_log WHERE query_id = '" + queryId + "'")) {
+                assertTrue("Query should be in query_log", rs.next());
+                assertEquals("Session ID should match", sessionId, rs.getString("session_id"));
+            }
+
+            final CountDownLatch queryStarted = new CountDownLatch(1);
+            Thread queryThread = new Thread(() -> {
+                try {
+                    queryStarted.countDown();
+                    stmt.executeQuery("SELECT sleep(10), number FROM system.numbers LIMIT 1000000");
+                } catch (SQLException e) {
+                    log.debug("Query was cancelled as expected", e);
+                }
+            });
+            queryThread.start();
+            queryStarted.await();
+            Thread.sleep(100); // Brief wait for query to start executing
+
+            // This should not throw "Session is locked by a concurrent client" error
+            stmt.cancel();
+            queryThread.join(5000);
+
+            // Verify statement is still usable after cancel
+            try (ResultSet rs = stmt.executeQuery("SELECT 1")) {
+                assertTrue(rs.next());
+                assertEquals(rs.getInt(1), 1);
+            }
+        }
+    }
+
     @Test(groups = {"integration"})
     public void testTextFormatInResponse() throws Exception {
         try (Connection conn = getJdbcConnection();