o Making some test cases.

16 files changed, 372 insertions, 614 deletions

diff --git a/src/main/java/io/trygvis/CreateArticleCallable.java b/src/main/java/io/trygvis/CreateArticleCallable.java
deleted file mode 100755
index 471b59d..0000000
--- a/src/main/java/io/trygvis/CreateArticleCallable.java
+++ /dev/null
@@ -1,42 +0,0 @@
-package io.trygvis;
-
-import io.trygvis.model.Article;
-import io.trygvis.async.AsyncService;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.stereotype.Component;
-import org.springframework.transaction.annotation.Transactional;
-
-import java.util.Date;
-import java.util.List;
-import java.util.Random;
-
-import static org.springframework.transaction.annotation.Propagation.MANDATORY;
-
-@Component("createArticle")
-@Transactional(propagation = MANDATORY)
-public class CreateArticleCallable implements AsyncService.AsyncCallable {
-    private final Logger log = LoggerFactory.getLogger(getClass());
-
-//    @PersistenceContext
-//    private EntityManager entityManager;
-
-    private Random random = new Random();
-
-    public void run(List<String> arguments) throws Exception {
-        log.info("CreateArticeJob.run: BEGIN");
-
-        if (random.nextInt() % 3 == 0) {
-            throw new RuntimeException("failing create article");
-        }
-
-        Date now = new Date();
-
-        log.info("now = {}", now);
-
-        Article article = new Article(new Date(), null, "title", "body");
-//        entityManager.persist(article);
-
-        log.info("CreateArticeJob.run: END");
-    }
-}
diff --git a/src/main/java/io/trygvis/Main.java b/src/main/java/io/trygvis/Main.java
deleted file mode 100755
index 08b9b75..0000000
--- a/src/main/java/io/trygvis/Main.java
+++ /dev/null
@@ -1,117 +0,0 @@
-package io.trygvis;
-
-import io.trygvis.async.AsyncService;
-import io.trygvis.queue.Queue;
-import io.trygvis.queue.Task;
-import org.hibernate.dialect.PostgreSQL82Dialect;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.slf4j.bridge.SLF4JBridgeHandler;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Qualifier;
-import org.springframework.context.support.ClassPathXmlApplicationContext;
-import org.springframework.stereotype.Component;
-import org.springframework.transaction.TransactionStatus;
-import org.springframework.transaction.support.TransactionCallbackWithoutResult;
-import org.springframework.transaction.support.TransactionTemplate;
-
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-
-import static java.lang.System.*;
-import static java.lang.Thread.sleep;
-
-@Component
-public class Main {
-    private static final Logger log = LoggerFactory.getLogger(Main.class);
-
-    public static void main(String[] args) throws Exception {
-        SLF4JBridgeHandler.install();
-
-        String username = getProperty("user.name");
-        setProperty("database.url", getProperty("jdbc.url", "jdbc:postgresql://localhost/" + username));
-        setProperty("database.username", username);
-        setProperty("database.password", username);
-//        setProperty("hibernate.showSql", "true");
-        setProperty("hibernate.hbm2ddl.auto", "create"); // create
-        setProperty("hibernate.dialect", PostgreSQL82Dialect.class.getName());
-
-        log.info("Starting context");
-        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
-        log.info("Started context");
-
-        try {
-            context.getBean(Main.class).run();
-//            log.info("Sleeping");
-//            sleep(1000 * 1000);
-        } catch (Exception e) {
-            e.printStackTrace(System.out);
-        }
-
-        log.info("Stopping context");
-        context.stop();
-        log.info("Stopped context");
-
-        exit(0);
-    }
-
-    @Autowired
-    private TransactionTemplate transactionTemplate;
-
-    @Autowired
-    private AsyncService asyncService;
-
-    @Autowired
-    @Qualifier("createArticle")
-    private AsyncService.AsyncCallable createArticleCallable;
-
-    @Autowired
-    @Qualifier("updateArticle")
-    private AsyncService.AsyncCallable updateArticleCallable;
-
-    public void run() throws Exception {
-        log.info("Main.run");
-
-        final Queue q = asyncService.registerQueue("create-article", 1, createArticleCallable);
-//        log.info("queue registered: ref = {}", q);
-//        asyncService.registerQueue("update-queue", 1, updateArticleCallable);
-
-//        q = asyncService.getQueue("create-queue");
-
-        final List<Task> tasks = new ArrayList<>();
-
-        final int count = 1;
-        log.info("Creating {} tasks", count);
-        transactionTemplate.execute(new TransactionCallbackWithoutResult() {
-            protected void doInTransactionWithoutResult(TransactionStatus status) {
-                for (int i = 0; i < count; i++) {
-                    tasks.add(asyncService.schedule(q));
-                }
-            }
-        });
-        log.info("Created {} tasks", count);
-
-        while (true) {
-            sleep(10000);
-
-            log.info("Checking for status of {} tasks", tasks.size());
-            for (Iterator<Task> iterator = tasks.iterator(); iterator.hasNext(); ) {
-                Task task = iterator.next();
-
-                task = asyncService.update(task);
-
-//                log.info("task = {}", task);
-
-                if (task.isDone()) {
-                    iterator.remove();
-                }
-            }
-
-            if (tasks.isEmpty()) {
-                log.info("No more tasks");
-                break;
-            }
-        }
-    }
-}
diff --git a/src/main/java/io/trygvis/UpdateArticleCallable.java b/src/main/java/io/trygvis/UpdateArticleCallable.java
deleted file mode 100755
index a910855..0000000
--- a/src/main/java/io/trygvis/UpdateArticleCallable.java
+++ /dev/null
@@ -1,44 +0,0 @@
-package io.trygvis;
-
-import io.trygvis.async.AsyncService;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.stereotype.Component;
-
-import java.util.Date;
-import java.util.List;
-import java.util.Random;
-
-@Component("updateArticle")
-public class UpdateArticleCallable
-    implements AsyncService.AsyncCallable {
-    private final Logger log = LoggerFactory.getLogger(getClass());
-
-    private final Random r = new Random();
-
-//    @PersistenceContext
-//    private EntityManager entityManager;
-
-//    @Transactional(propagation = REQUIRES_NEW)
-    public void run(List<String> arguments) throws Exception {
-        log.info("UpdateArticeJob.run: BEGIN");
-
-        Date now = new Date();
-
-        log.info("now = {}", now);
-
-/*
-        TypedQuery<Article> q = entityManager.createQuery(entityManager.getCriteriaBuilder().createQuery(Article.class));
-
-        List<Article> list = q.getResultList();
-        log.info("Got {} articles", list.size());
-
-        Article a = list.get(r.nextInt(list.size()));
-        a.setUpdated(new Date());
-
-        entityManager.persist(a);
-*/
-
-        log.info("UpdateArticeJob.run: END");
-    }
-}
diff --git a/src/main/java/io/trygvis/async/AsyncService.java b/src/main/java/io/trygvis/async/AsyncService.java
index e90a0e4..57c1af8 100755
--- a/src/main/java/io/trygvis/async/AsyncService.java
+++ b/src/main/java/io/trygvis/async/AsyncService.java
@@ -2,8 +2,8 @@ package io.trygvis.async;
 
 import io.trygvis.queue.Queue;
 import io.trygvis.queue.Task;
-import org.quartz.SchedulerException;
 
+import java.sql.SQLException;
 import java.util.List;
 
 /**
@@ -16,9 +16,8 @@ public interface AsyncService {
      * @param interval how often the queue should be polled for missed tasks in seconds.
      * @param callable
      * @return
-     * @throws SchedulerException
      */
-    Queue registerQueue(String name, int interval, AsyncCallable callable) throws SchedulerException;
+    Queue registerQueue(final String name, final int interval, AsyncCallable callable);
 
     Queue getQueue(String name);
 
diff --git a/src/main/java/io/trygvis/async/JdbcAsyncService.java b/src/main/java/io/trygvis/async/JdbcAsyncService.java
index 4e78a37..c34330e 100644
--- a/src/main/java/io/trygvis/async/JdbcAsyncService.java
+++ b/src/main/java/io/trygvis/async/JdbcAsyncService.java
@@ -4,88 +4,66 @@ import io.trygvis.queue.Queue;
 import io.trygvis.queue.QueueDao;
 import io.trygvis.queue.Task;
 import io.trygvis.queue.TaskDao;
-import org.quartz.SchedulerException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.stereotype.Component;
-import org.springframework.transaction.annotation.Transactional;
-import org.springframework.transaction.support.TransactionSynchronization;
-import org.springframework.transaction.support.TransactionSynchronizationAdapter;
-import org.springframework.transaction.support.TransactionTemplate;
 
+import java.sql.Connection;
+import java.sql.SQLException;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledThreadPoolExecutor;
 
 import static java.lang.System.currentTimeMillis;
 import static java.lang.Thread.sleep;
 import static java.util.Arrays.asList;
 import static java.util.concurrent.TimeUnit.SECONDS;
-import static org.springframework.transaction.annotation.Propagation.REQUIRED;
-import static org.springframework.transaction.support.TransactionSynchronizationManager.registerSynchronization;
 
-@Component
-public class JdbcAsyncService implements AsyncService {
+public class JdbcAsyncService {
     private final Logger log = LoggerFactory.getLogger(getClass());
 
-    private final ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(10, Executors.defaultThreadFactory());
-
     private final Map<String, QueueThread> queues = new HashMap<>();
 
-    @Autowired
-    private TransactionTemplate transactionTemplate;
-
-    @Autowired
-    private QueueDao queueDao;
-
-    @Autowired
-    private TaskDao taskDao;
+    public Queue registerQueue(Connection c, SqlEffectExecutor sqlEffectExecutor, final String name, final int interval, AsyncService.AsyncCallable callable) throws SQLException {
+        QueueDao queueDao = new QueueDao(c);
 
-    @Transactional(propagation = REQUIRED)
-    public Queue registerQueue(final String name, final int interval, AsyncCallable callable) throws SchedulerException {
         log.info("registerQueue: ENTER");
 
         Queue q = queueDao.findByName(name);
 
         log.info("q = {}", q);
 
-        final long interval_;
         if (q == null) {
             q = new Queue(name, interval);
             queueDao.insert(q);
-            interval_ = interval;
-        } else {
-            // Found an existing queue. Use the Settings from the database.
-            interval_ = q.interval;
         }
 
-        final QueueThread queueThread = new QueueThread(q, taskDao, transactionTemplate, callable);
+        final QueueThread queueThread = new QueueThread(sqlEffectExecutor, callable, q);
         queues.put(name, queueThread);
 
-        registerSynchronization(new TransactionSynchronizationAdapter() {
-            public void afterCompletion(int status) {
-                log.info("Transaction completed with status = {}", status);
-                if (status == TransactionSynchronization.STATUS_COMMITTED) {
-                    log.info("Starting thread for queue {} with poll interval = {}s", name, interval);
-                    executor.scheduleAtFixedRate(new Runnable() {
-                        public void run() {
-                            queueThread.ping();
-                        }
-                    }, 10, interval_, SECONDS);
-                    Thread thread = new Thread(queueThread, name);
-                    thread.setDaemon(true);
-                    thread.start();
-                }
-            }
-        });
-
         log.info("registerQueue: LEAVE");
         return q;
     }
 
+    public void startQueue(ScheduledThreadPoolExecutor executor, String name) {
+        final QueueThread queueThread = queues.get(name);
+
+        if (queueThread == null) {
+            throw new RuntimeException("No such queue: " + name);
+        }
+
+        long interval = queueThread.queue.interval;
+        log.info("Starting thread for queue {} with poll interval = {}s", name, interval);
+        executor.scheduleAtFixedRate(new Runnable() {
+            public void run() {
+                queueThread.ping();
+            }
+        }, 10, interval, SECONDS);
+        Thread thread = new Thread(queueThread, name);
+        thread.setDaemon(true);
+        thread.start();
+    }
+
     public Queue getQueue(String name) {
         QueueThread queueThread = queues.get(name);
 
@@ -96,16 +74,17 @@ public class JdbcAsyncService implements AsyncService {
         return queueThread.queue;
     }
 
-    @Transactional(propagation = REQUIRED)
-    public Task schedule(final Queue queue, String... args) {
-        return scheduleInner(null, queue, args);
+    public Task schedule(Connection c, final Queue queue, String... args) throws SQLException {
+        return scheduleInner(c, null, queue, args);
     }
 
-    public Task schedule(long parent, Queue queue, String... args) {
-        return scheduleInner(parent, queue, args);
+    public Task schedule(Connection c, long parent, Queue queue, String... args) throws SQLException {
+        return scheduleInner(c, parent, queue, args);
     }
 
-    private Task scheduleInner(Long parent, final Queue queue, String... args) {
+    private Task scheduleInner(Connection c, Long parent, final Queue queue, String... args) throws SQLException {
+        TaskDao taskDao = new TaskDao(c);
+
         Date scheduled = new Date();
 
         StringBuilder arguments = new StringBuilder();
@@ -114,27 +93,22 @@ public class JdbcAsyncService implements AsyncService {
         }
 
         long id = taskDao.insert(parent, queue.name, scheduled, arguments.toString());
-        Task task = new Task(parent, id, queue.name, scheduled, null, 0, null, asList(args));
+        Task task = new Task(id, parent, queue.name, scheduled, null, 0, null, asList(args));
         log.info("Created task = {}", task);
 
-        registerSynchronization(new TransactionSynchronizationAdapter() {
-            public void afterCompletion(int status) {
-                if (status == TransactionSynchronization.STATUS_COMMITTED) {
-                    queues.get(queue.name).ping();
-                }
-            }
-        });
-
         return task;
     }
 
-    @Transactional
-    public Task await(Task task, long timeout) {
+    public Task await(Connection c, Task task, long timeout) throws SQLException {
         final long start = currentTimeMillis();
         final long end = start + timeout;
 
         while (currentTimeMillis() < end) {
-            task = update(task);
+            task = update(c, task);
+
+            if (task == null) {
+                throw new RuntimeException("The task went away.");
+            }
 
             try {
                 sleep(100);
@@ -146,8 +120,9 @@ public class JdbcAsyncService implements AsyncService {
         return task;
     }
 
-    @Transactional(readOnly = true)
-    public Task update(Task ref) {
+    public Task update(Connection c, Task ref) throws SQLException {
+        TaskDao taskDao = new TaskDao(c);
+
         return taskDao.findById(ref.id);
     }
 }
diff --git a/src/main/java/io/trygvis/async/QueueThread.java b/src/main/java/io/trygvis/async/QueueThread.java
index 69466df..00c46b4 100644
--- a/src/main/java/io/trygvis/async/QueueThread.java
+++ b/src/main/java/io/trygvis/async/QueueThread.java
@@ -5,37 +5,33 @@ import io.trygvis.queue.Task;
 import io.trygvis.queue.TaskDao;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.transaction.TransactionException;
-import org.springframework.transaction.TransactionStatus;
-import org.springframework.transaction.support.TransactionCallback;
-import org.springframework.transaction.support.TransactionCallbackWithoutResult;
-import org.springframework.transaction.support.TransactionTemplate;
 
+import java.sql.Connection;
+import java.sql.SQLException;
 import java.util.Date;
 import java.util.List;
 
+import static io.trygvis.async.SqlEffectExecutor.SqlExecutionException;
+
 class QueueThread implements Runnable {
     private final Logger log = LoggerFactory.getLogger(getClass());
 
-    public boolean shouldRun = true;
-
-    private boolean checkForNewTasks;
+    private final SqlEffectExecutor sqlEffectExecutor;
 
-    private boolean busy;
+    private final AsyncService.AsyncCallable callable;
 
     public final Queue queue;
 
-    private final TaskDao taskDao;
+    public boolean shouldRun = true;
 
-    private final TransactionTemplate transactionTemplate;
+    private boolean checkForNewTasks;
 
-    private final AsyncService.AsyncCallable callable;
+    private boolean busy;
 
-    QueueThread(Queue queue, TaskDao taskDao, TransactionTemplate transactionTemplate, AsyncService.AsyncCallable callable) {
-        this.queue = queue;
-        this.taskDao = taskDao;
-        this.transactionTemplate = transactionTemplate;
+    QueueThread(SqlEffectExecutor sqlEffectExecutor, AsyncService.AsyncCallable callable, Queue queue) {
+        this.sqlEffectExecutor = sqlEffectExecutor;
         this.callable = callable;
+        this.queue = queue;
     }
 
     public void ping() {
@@ -52,19 +48,25 @@ class QueueThread implements Runnable {
     public void run() {
         while (shouldRun) {
             try {
-                List<Task> tasks = transactionTemplate.execute(new TransactionCallback<List<Task>>() {
-                    public List<Task> doInTransaction(TransactionStatus status) {
-                        return taskDao.findByNameAndCompletedIsNull(queue.name);
+//                List<Task> tasks = transactionTemplate.execute(new TransactionCallback<List<Task>>() {
+//                    public List<Task> doInTransaction(TransactionStatus status) {
+//                        return taskDao.findByNameAndCompletedIsNull(queue.name);
+//                    }
+//                });
+                List<Task> tasks = sqlEffectExecutor.execute(new SqlEffect<List<Task>>() {
+                    @Override
+                    public List<Task> doInConnection(Connection connection) throws SQLException {
+                        return new TaskDao(connection).findByNameAndCompletedIsNull(queue.name);
                     }
                 });
 
                 log.info("Found {} tasks on queue {}", tasks.size(), queue.name);
 
-                if(tasks.size() > 0) {
+                if (tasks.size() > 0) {
                     for (final Task task : tasks) {
                         try {
                             executeTask(task);
-                        } catch (TransactionException | TaskFailureException e) {
+                        } catch (SqlExecutionException | TaskFailureException e) {
                             log.warn("Task execution failed", e);
                         }
                     }
@@ -96,24 +98,44 @@ class QueueThread implements Runnable {
     private void executeTask(final Task task) {
         final Date run = new Date();
         log.info("Setting last run on task. date = {}, task = {}", run, task);
-        transactionTemplate.execute(new TransactionCallbackWithoutResult() {
-            protected void doInTransactionWithoutResult(TransactionStatus status) {
-                taskDao.update(task.registerRun());
+        sqlEffectExecutor.execute(new SqlEffect.Void() {
+            @Override
+            public void doInConnection(Connection connection) throws SQLException {
+                new TaskDao(connection).update(task.registerRun());
             }
         });
-
-        transactionTemplate.execute(new TransactionCallbackWithoutResult() {
-            protected void doInTransactionWithoutResult(TransactionStatus status) {
+//        transactionTemplate.execute(new TransactionCallbackWithoutResult() {
+//            protected void doInTransactionWithoutResult(TransactionStatus status) {
+//                taskDao.update(task.registerRun());
+//            }
+//        });
+
+        sqlEffectExecutor.execute(new SqlEffect.Void() {
+            @Override
+            public void doInConnection(Connection c) throws SQLException {
                 try {
                     callable.run(task.arguments);
                     Date completed = new Date();
                     Task t = task.registerComplete(completed);
                     log.info("Completed task: {}", t);
-                    taskDao.update(t);
+                    new TaskDao(c).update(t);
                 } catch (Exception e) {
                     throw new TaskFailureException(e);
                 }
             }
         });
+//        transactionTemplate.execute(new TransactionCallbackWithoutResult() {
+//            protected void doInTransactionWithoutResult(TransactionStatus status) {
+//                try {
+//                    callable.run(task.arguments);
+//                    Date completed = new Date();
+//                    Task t = task.registerComplete(completed);
+//                    log.info("Completed task: {}", t);
+//                    taskDao.update(t);
+//                } catch (Exception e) {
+//                    throw new TaskFailureException(e);
+//                }
+//            }
+//        });
     }
 }
diff --git a/src/main/java/io/trygvis/async/SqlEffect.java b/src/main/java/io/trygvis/async/SqlEffect.java
new file mode 100644
index 0000000..d0c4e9b
--- /dev/null
+++ b/src/main/java/io/trygvis/async/SqlEffect.java
@@ -0,0 +1,12 @@
+package io.trygvis.async;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+public interface SqlEffect<A> {
+    A doInConnection(Connection c) throws SQLException;
+
+    interface Void {
+        void doInConnection(Connection c) throws SQLException;
+    }
+}
diff --git a/src/main/java/io/trygvis/async/SqlEffectExecutor.java b/src/main/java/io/trygvis/async/SqlEffectExecutor.java
new file mode 100644
index 0000000..c8abbd3
--- /dev/null
+++ b/src/main/java/io/trygvis/async/SqlEffectExecutor.java
@@ -0,0 +1,39 @@
+package io.trygvis.async;
+
+import javax.sql.DataSource;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+public class SqlEffectExecutor {
+
+    private final DataSource dataSource;
+
+    public SqlEffectExecutor(DataSource dataSource) {
+        this.dataSource = dataSource;
+    }
+
+    public <A> A execute(SqlEffect<A> effect) {
+        try (Connection c = dataSource.getConnection()) {
+            return effect.doInConnection(c);
+        } catch (SQLException e) {
+            throw new SqlExecutionException(e);
+        }
+    }
+
+    public void execute(SqlEffect.Void effect) {
+        try (Connection c = dataSource.getConnection()) {
+            effect.doInConnection(c);
+        } catch (SQLException e) {
+            throw new SqlExecutionException(e);
+        }
+    }
+
+    public static class SqlExecutionException extends RuntimeException {
+        public final SQLException exception;
+
+        public SqlExecutionException(SQLException ex) {
+            super(ex);
+            this.exception = ex;
+        }
+    }
+}
diff --git a/src/main/java/io/trygvis/async/spring/SpringJdbcAsyncService.java b/src/main/java/io/trygvis/async/spring/SpringJdbcAsyncService.java
new file mode 100644
index 0000000..8517c68
--- /dev/null
+++ b/src/main/java/io/trygvis/async/spring/SpringJdbcAsyncService.java
@@ -0,0 +1,102 @@
+package io.trygvis.async.spring;
+
+import io.trygvis.async.AsyncService;
+import io.trygvis.async.JdbcAsyncService;
+import io.trygvis.async.SqlEffectExecutor;
+import io.trygvis.queue.Queue;
+import io.trygvis.queue.Task;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.jdbc.core.ConnectionCallback;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.transaction.support.TransactionSynchronization;
+import org.springframework.transaction.support.TransactionSynchronizationAdapter;
+import org.springframework.transaction.support.TransactionTemplate;
+
+import javax.annotation.PostConstruct;
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+
+import static org.springframework.transaction.annotation.Propagation.REQUIRED;
+import static org.springframework.transaction.support.TransactionSynchronizationManager.registerSynchronization;
+
+public class SpringJdbcAsyncService implements AsyncService {
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    private final ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(10, Executors.defaultThreadFactory());
+
+    private final TransactionTemplate transactionTemplate;
+
+    private final JdbcTemplate jdbcTemplate;
+
+    private SqlEffectExecutor sqlEffectExecutor;
+
+    final JdbcAsyncService jdbcAsyncService;
+
+    public SpringJdbcAsyncService(TransactionTemplate transactionTemplate, JdbcTemplate jdbcTemplate) {
+        this.transactionTemplate = transactionTemplate;
+        this.jdbcTemplate = jdbcTemplate;
+        jdbcAsyncService = new JdbcAsyncService();
+        sqlEffectExecutor = new SqlEffectExecutor(this.jdbcTemplate.getDataSource());
+    }
+
+    @Transactional(propagation = REQUIRED)
+    public Queue registerQueue(final String name, final int interval, final AsyncService.AsyncCallable callable) {
+        return jdbcTemplate.execute(new ConnectionCallback<Queue>() {
+            @Override
+            public Queue doInConnection(Connection c) throws SQLException {
+
+                Queue q = jdbcAsyncService.registerQueue(c, sqlEffectExecutor, name, interval, callable);
+
+                registerSynchronization(new TransactionSynchronizationAdapter() {
+                    public void afterCompletion(int status) {
+                        log.info("Transaction completed with status = {}", status);
+                        if (status == TransactionSynchronization.STATUS_COMMITTED) {
+                            jdbcAsyncService.startQueue(executor, name);
+                        }
+                    }
+                });
+
+                log.info("registerQueue: LEAVE");
+                return q;
+            }
+        });
+    }
+
+    public Queue getQueue(String name) {
+        return jdbcAsyncService.getQueue(name);
+    }
+
+    @Transactional(propagation = REQUIRED)
+    public Task schedule(final Queue queue, final String... args) {
+        return jdbcTemplate.execute(new ConnectionCallback<Task>() {
+            @Override
+            public Task doInConnection(Connection c) throws SQLException {
+                return jdbcAsyncService.schedule(c, queue, args);
+            }
+        });
+    }
+
+    public Task schedule(final long parent, final Queue queue, final String... args) {
+        return jdbcTemplate.execute(new ConnectionCallback<Task>() {
+            @Override
+            public Task doInConnection(Connection c) throws SQLException {
+                return jdbcAsyncService.schedule(c, parent, queue, args);
+            }
+        });
+    }
+
+    @Transactional(readOnly = true)
+    public Task update(final Task ref) {
+        return jdbcTemplate.execute(new ConnectionCallback<Task>() {
+            @Override
+            public Task doInConnection(Connection c) throws SQLException {
+                return jdbcAsyncService.update(c, ref);
+            }
+        });
+    }
+}
diff --git a/src/main/java/io/trygvis/model/Article.java b/src/main/java/io/trygvis/model/Article.java
deleted file mode 100755
index e86c570..0000000
--- a/src/main/java/io/trygvis/model/Article.java
+++ /dev/null
@@ -1,55 +0,0 @@
-package io.trygvis.model;
-
-import javax.persistence.Entity;
-import javax.persistence.GeneratedValue;
-import javax.persistence.GenerationType;
-import javax.persistence.Id;
-import javax.persistence.SequenceGenerator;
-import java.util.Date;
-
-@Entity
-public class Article {
-    @Id
-    @SequenceGenerator(name="id_seq", sequenceName="id_seq")
-    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "id_seq")
-    private Integer id;
-    private Date created;
-    private Date updated;
-    private String title;
-    private String body;
-
-    @SuppressWarnings("UnusedDeclaration")
-    private Article() {
-    }
-
-    public Article(Date created, Date updated, String title, String body) {
-        this.created = created;
-        this.updated = updated;
-        this.title = title;
-        this.body = body;
-    }
-
-    public Integer getId() {
-        return id;
-    }
-
-    public Date getCreated() {
-        return created;
-    }
-
-    public Date getUpdated() {
-        return updated;
-    }
-
-    public void setUpdated(Date updated) {
-        this.updated = updated;
-    }
-
-    public String getTitle() {
-        return title;
-    }
-
-    public String getBody() {
-        return body;
-    }
-}
diff --git a/src/main/java/io/trygvis/queue/QueueDao.java b/src/main/java/io/trygvis/queue/QueueDao.java
index 63dde2a..2f69e11 100644
--- a/src/main/java/io/trygvis/queue/QueueDao.java
+++ b/src/main/java/io/trygvis/queue/QueueDao.java
@@ -1,36 +1,45 @@
 package io.trygvis.queue;
 
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.jdbc.core.JdbcTemplate;
-import org.springframework.jdbc.core.RowMapper;
-import org.springframework.stereotype.Component;
-
+import java.sql.Connection;
+import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
-import static org.springframework.dao.support.DataAccessUtils.singleResult;
-
-@Component
 public class QueueDao {
 
-    @Autowired
-    private JdbcTemplate jdbcTemplate;
+    private final Connection connection;
 
-    public Queue findByName(String name) {
-        return singleResult(jdbcTemplate.query("SELECT name, interval FROM queue WHERE name=?", new QueueRowMapper(), name));
+    public QueueDao(Connection connection) {
+        this.connection = connection;
     }
 
-    public void insert(Queue q) {
-        jdbcTemplate.update("INSERT INTO queue(name, interval) VALUES(?, ?)", q.name, q.interval);
+    public Queue findByName(String name) throws SQLException {
+        try (PreparedStatement stmt = connection.prepareStatement("SELECT name, interval FROM queue WHERE name=?")) {
+            stmt.setString(1, name);
+            ResultSet rs = stmt.executeQuery();
+            return rs.next() ? mapRow(rs) : null;
+        }
     }
 
-    public void update(Queue q) {
-        jdbcTemplate.update("UPDATE queue SET interval=? WHERE name=?", q.interval, q.name);
+    public void insert(Queue q) throws SQLException {
+        try (PreparedStatement stmt = connection.prepareStatement("INSERT INTO queue(name, interval) VALUES(?, ?)")) {
+            int i = 1;
+            stmt.setString(i++, q.name);
+            stmt.setLong(i, q.interval);
+            stmt.executeUpdate();
+        }
     }
 
-    private class QueueRowMapper implements RowMapper<Queue> {
-        public Queue mapRow(ResultSet rs, int rowNum) throws SQLException {
-            return new Queue(rs.getString(1), rs.getLong(2));
+    public void update(Queue q) throws SQLException {
+        try (PreparedStatement stmt = connection.prepareStatement("UPDATE queue SET interval=? WHERE name=?")) {
+            int i = 1;
+            stmt.setLong(i++, q.interval);
+            stmt.setString(i, q.name);
+            stmt.executeUpdate();
         }
     }
+
+    public Queue mapRow(ResultSet rs) throws SQLException {
+        return new Queue(rs.getString(1), rs.getLong(2));
+    }
 }
diff --git a/src/main/java/io/trygvis/queue/TaskDao.java b/src/main/java/io/trygvis/queue/TaskDao.java
index a59dcbb..5459933 100644
--- a/src/main/java/io/trygvis/queue/TaskDao.java
+++ b/src/main/java/io/trygvis/queue/TaskDao.java
@@ -1,69 +1,104 @@
 package io.trygvis.queue;
 
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.jdbc.core.JdbcTemplate;
-import org.springframework.jdbc.core.RowMapper;
-import org.springframework.stereotype.Component;
-import org.springframework.transaction.annotation.Transactional;
-
+import java.sql.Connection;
+import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.sql.Timestamp;
+import java.sql.Types;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 
 import static java.util.Arrays.asList;
-import static org.springframework.transaction.annotation.Propagation.MANDATORY;
 
-@Component
 public class TaskDao {
 
-    @Autowired
-    private JdbcTemplate jdbcTemplate;
+    private final Connection connection;
+
+    public static final String fields = "id, parent, queue, scheduled, last_run, run_count, completed, arguments";
 
-    public long insert(String queue, Date scheduled, String arguments) {
-        return this.insert(null, queue, scheduled, arguments);
+    public TaskDao(Connection connection) {
+        this.connection = connection;
     }
 
-    @Transactional(propagation = MANDATORY)
-    public long insert(Long parent, String queue, Date scheduled, String arguments) {
-        jdbcTemplate.update("INSERT INTO task(id, parent, run_count, queue, scheduled, arguments) " +
-                "VALUES(nextval('task_seq'), ?, 0, ?, ?, ?)", parent, queue, scheduled, arguments);
-        return jdbcTemplate.queryForObject("SELECT currval('task_seq')", Long.class);
+    public long insert(String queue, Date scheduled, String arguments) throws SQLException {
+        return insert(null, queue, scheduled, arguments);
     }
 
-    @Transactional(propagation = MANDATORY)
-    public Task findById(long id) {
-        return jdbcTemplate.queryForObject("SELECT " + TaskRowMapper.fields + " FROM task WHERE id=?",
-                new TaskRowMapper(), id);
+    public long insert(Long parent, String queue, Date scheduled, String arguments) throws SQLException {
+        String sql = "INSERT INTO task(id, parent, run_count, queue, scheduled, arguments) " +
+                "VALUES(nextval('task_seq'), ?, 0, ?, ?, ?)";
+        try (PreparedStatement stmt = connection.prepareStatement(sql)) {
+            int i = 1;
+            if (parent == null) {
+                stmt.setNull(i++, Types.BIGINT);
+            } else {
+                stmt.setLong(i++, parent);
+            }
+            stmt.setString(i++, queue);
+            stmt.setTimestamp(i++, new Timestamp(scheduled.getTime()));
+            stmt.setString(i, arguments);
+            stmt.executeUpdate();
+        }
+        try (PreparedStatement stmt = connection.prepareStatement("SELECT currval('task_seq')")) {
+            ResultSet rs = stmt.executeQuery();
+            rs.next();
+            return rs.getLong(1);
+        }
     }
 
-    @Transactional(propagation = MANDATORY)
-    public List<Task> findByNameAndCompletedIsNull(String name) {
-        return jdbcTemplate.query("SELECT " + TaskRowMapper.fields + " FROM task WHERE queue=? AND completed IS NULL",
-                new TaskRowMapper(), name);
+    public Task findById(long id) throws SQLException {
+        try (PreparedStatement stmt = connection.prepareStatement("SELECT " + fields + " FROM task WHERE id=?")) {
+            ResultSet rs = stmt.executeQuery();
+            return rs.next() ? mapRow(rs) : null;
+        }
     }
 
-    @Transactional(propagation = MANDATORY)
-    public void update(Task task) {
-        jdbcTemplate.update("UPDATE task SET scheduled=?, last_run=?, run_count=?, completed=? WHERE id=?",
-                task.scheduled, task.lastRun, task.runCount, task.completed, task.id);
+    public List<Task> findByNameAndCompletedIsNull(String name) throws SQLException {
+        try (PreparedStatement stmt = connection.prepareStatement("SELECT " + fields + " FROM task WHERE queue=? AND completed IS NULL")) {
+            int i = 1;
+            stmt.setString(i, name);
+            ResultSet rs = stmt.executeQuery();
+            List<Task> list = new ArrayList<>();
+            while (rs.next()) {
+                list.add(mapRow(rs));
+            }
+            return list;
+        }
     }
 
-    private class TaskRowMapper implements RowMapper<Task> {
-        public static final String fields = "id, parent, queue, scheduled, last_run, run_count, completed, arguments";
+    public void update(Task task) throws SQLException {
+        try (PreparedStatement stmt = connection.prepareStatement("UPDATE task SET scheduled=?, last_run=?, run_count=?, completed=? WHERE id=?")) {
+            int i = 1;
+            stmt.setTimestamp(i++, new Timestamp(task.scheduled.getTime()));
+            setTimestamp(stmt, i++, task.lastRun);
+            stmt.setInt(i++, task.runCount);
+            setTimestamp(stmt, i++, task.completed);
+            stmt.setLong(i, task.id);
+            stmt.executeUpdate();
+        }
+    }
 
-        public Task mapRow(ResultSet rs, int rowNum) throws SQLException {
-            String arguments = rs.getString(8);
-            return new Task(
-                    rs.getLong(1),
-                    rs.getLong(2),
-                    rs.getString(3),
-                    rs.getTimestamp(4),
-                    rs.getTimestamp(5),
-                    rs.getInt(6),
-                    rs.getTimestamp(7),
-                    arguments != null ? asList(arguments.split(" ")) : Collections.<String>emptyList());
+    private static void setTimestamp(PreparedStatement stmt, int parameterIndex, Date date) throws SQLException {
+        if (date == null) {
+            stmt.setNull(parameterIndex, Types.TIMESTAMP);
+        } else {
+            stmt.setTimestamp(parameterIndex, new Timestamp(date.getTime()));
         }
     }
+
+    public Task mapRow(ResultSet rs) throws SQLException {
+        String arguments = rs.getString(8);
+        return new Task(
+                rs.getLong(1),
+                rs.getLong(2),
+                rs.getString(3),
+                rs.getTimestamp(4),
+                rs.getTimestamp(5),
+                rs.getInt(6),
+                rs.getTimestamp(7),
+                arguments != null ? asList(arguments.split(" ")) : Collections.<String>emptyList());
+    }
 }
diff --git a/src/main/java/io/trygvis/spring/Config.java b/src/main/java/io/trygvis/spring/Config.java
deleted file mode 100755
index df4b2e2..0000000
--- a/src/main/java/io/trygvis/spring/Config.java
+++ /dev/null
@@ -1,172 +0,0 @@
-package io.trygvis.spring;
-
-import com.jolbox.bonecp.BoneCPDataSource;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.ComponentScan;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
-import org.springframework.jdbc.core.JdbcTemplate;
-import org.springframework.jdbc.datasource.DataSourceTransactionManager;
-import org.springframework.jdbc.datasource.LazyConnectionDataSourceProxy;
-import org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy;
-import org.springframework.transaction.PlatformTransactionManager;
-import org.springframework.transaction.annotation.EnableTransactionManagement;
-import org.springframework.transaction.support.TransactionTemplate;
-
-import javax.sql.DataSource;
-
-@Configuration
-@ComponentScan(basePackages = "io.trygvis")
-@EnableTransactionManagement
-//@EnableJpaRepositories(basePackages = "io.trygvis.data")
-public class Config {
-
-    @Bean
-    public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() throws Exception {
-        return new PropertySourcesPlaceholderConfigurer() {{
-//            setLocation(new UrlResource("file:environment.properties"));
-            setProperties(System.getProperties());
-            setLocalOverride(true);
-        }};
-    }
-
-    @Bean
-    public JdbcTemplate jdbcTemplate(DataSource dataSource) {
-        return new JdbcTemplate(dataSource);
-    }
-
-//    public SpringBeanJobFactory springBeanJobFactory() {
-//        SpringBeanJobFactory factory = new SpringBeanJobFactory();
-//        return factory;
-//    }
-
-/*
-    @Bean
-    public SchedulerFactoryBean quartz(DataSource dataSource, PlatformTransactionManager transactionManager) {
-        SchedulerFactoryBean bean = new SchedulerFactoryBean();
-        bean.setApplicationContextSchedulerContextKey("applicationContext");
-        bean.setDataSource(dataSource);
-        bean.setTransactionManager(transactionManager);
-//        bean.setJobFactory(new JobFactory() {
-//            public Job newJob(TriggerFiredBundle bundle, Scheduler scheduler) throws SchedulerException {
-//                Class<? extends Job> klass = bundle.getJobDetail().getJobClass();
-//            }
-//        });
-
-        Properties quartzProperties = new Properties();
-        quartzProperties.setProperty("org.quartz.scheduler.skipUpdateCheck", "true");
-//        quartzProperties.setProperty("org.quartz.jobStore.selectWithLockSQL", "false");
-        quartzProperties.setProperty("org.quartz.jobStore.driverDelegateClass", PostgreSQLDelegate.class.getName());
-        quartzProperties.setProperty("org.quartz.scheduler.jmx.export", "true");
-        bean.setQuartzProperties(quartzProperties);
-        return bean;
-    }
-*/
-
-    // This turns out to be fairly useless as Spring won't register them automatically.
-    // It's probably better to use @Scheduled/@Async instead
-    /*
-    @Bean(name = "my-job")
-    public JobDetailFactoryBean myJobDetailBean() {
-        JobDetailFactoryBean bean = new JobDetailFactoryBean();
-        bean.setJobClass(MyJob.class);
-        bean.setDurability(true);
-
-        return bean;
-    }
-
-    @Bean
-    public CronTriggerFactoryBean myJobTrigger(JobDetail jobDetail) {
-        CronTriggerFactoryBean bean = new CronTriggerFactoryBean();
-        bean.setName("my-trigger");
-        bean.setBeanName("my-job");
-        bean.setJobDetail(jobDetail);
-        bean.setCronExpression("0/10 * * * * ?");
-
-        return bean;
-    }
-    */
-
-    @Bean
-    public DataSource dataSource(@Value("${database.url}") String jdbcUrl,
-                                 @Value("${database.username}") String username,
-                                 @Value("${database.password}") String password) {
-        BoneCPDataSource ds = new BoneCPDataSource();
-
-        ds.setLogStatementsEnabled(true);
-
-        ds.setJdbcUrl(jdbcUrl);
-        ds.setUsername(username);
-        ds.setPassword(password);
-
-        ds.setIdleConnectionTestPeriodInSeconds(60);
-        ds.setIdleMaxAgeInSeconds(240);
-        ds.setMaxConnectionsPerPartition(40);
-        ds.setMinConnectionsPerPartition(0);
-        ds.setPartitionCount(1);
-        ds.setAcquireIncrement(1);
-        ds.setStatementsCacheSize(1000);
-        ds.setReleaseHelperThreads(3);
-        ds.setStatisticsEnabled(true);
-        return new TransactionAwareDataSourceProxy(new LazyConnectionDataSourceProxy(ds));
-    }
-
-/*
-    @Bean
-    public LocalContainerEntityManagerFactoryBean entityManagerFactory(DataSource dataSource,
-                                                                       @Value("${hibernate.hbm2ddl.auto}") String hbm2ddl,
-                                                                       @Value("${hibernate.showSql:false}") boolean showSql,
-                                                                       @Value("${hibernate.dialect}") String dialect) {
-        LocalContainerEntityManagerFactoryBean x = new LocalContainerEntityManagerFactoryBean();
-        x.setDataSource(dataSource);
-        x.setJpaPropertyMap(createJpaMap(hbm2ddl, showSql, dialect));
-        x.setPackagesToScan(Article.class.getPackage().getName());
-        HibernatePersistence persistenceProvider = new HibernatePersistence();
-        x.setPersistenceProvider(persistenceProvider);
-        return x;
-    }
-
-    public static Map<String, Object> createJpaMap(String hbm2ddl, boolean showSql, String dialect) {
-        Map<String, Object> map = new HashMap<>();
-        map.put(HBM2DDL_AUTO, hbm2ddl);
-        map.put(FORMAT_SQL, showSql);
-        map.put(SHOW_SQL, showSql);
-        map.put(USE_SQL_COMMENTS, showSql);
-        map.put(GENERATE_STATISTICS, true);
-        map.put(NAMING_STRATEGY, ImprovedNamingStrategy.class.getName());
-
-        map.put(DEFAULT_CACHE_CONCURRENCY_STRATEGY, CacheConcurrencyStrategy.READ_WRITE.toString());
-        map.put(CURRENT_SESSION_CONTEXT_CLASS, SpringSessionContext.class.getName());
-//        map.put(CACHE_REGION_FACTORY, EhCacheRegionFactory.class.getName());
-        map.put(USE_SECOND_LEVEL_CACHE, false);
-        map.put(USE_QUERY_CACHE, false);
-//        map.put(SHARED_CACHE_MODE, SharedCacheMode.ENABLE_SELECTIVE.toString());
-
-        map.put(DIALECT, dialect);
-        map.put("hibernate.temp.use_jdbc_metadata_defaults", "false");
-
-        return map;
-    }
-
-    @Bean
-    public SessionFactory sessionFactory(LocalContainerEntityManagerFactoryBean entityManagerFactory) {
-        return ((HibernateEntityManagerFactory) entityManagerFactory.nativeEntityManagerFactory).getSessionFactory();
-    }
-
-    @Bean
-    public JpaTransactionManager transactionManager(EntityManagerFactory entityManagerFactory) {
-        return new JpaTransactionManager(entityManagerFactory);
-    }
-*/
-
-    @Bean
-    public PlatformTransactionManager transactionManager(DataSource dataSource) {
-        return new DataSourceTransactionManager(dataSource);
-    }
-
-    @Bean
-    public TransactionTemplate transactionTemplate(PlatformTransactionManager platformTransactionManager) {
-        return new TransactionTemplate(platformTransactionManager);
-    }
-}
diff --git a/src/main/java/io/trygvis/spring/DefaultConfig.java b/src/main/java/io/trygvis/spring/DefaultConfig.java
new file mode 100644
index 0000000..af8f644
--- /dev/null
+++ b/src/main/java/io/trygvis/spring/DefaultConfig.java
@@ -0,0 +1,17 @@
+package io.trygvis.spring;
+
+import io.trygvis.async.AsyncService;
+import io.trygvis.async.spring.SpringJdbcAsyncService;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.transaction.support.TransactionTemplate;
+
+@Configuration
+public class DefaultConfig {
+
+    @Bean
+    public AsyncService asyncService(TransactionTemplate transactionTemplate, JdbcTemplate jdbcTemplate) {
+        return new SpringJdbcAsyncService(transactionTemplate, jdbcTemplate);
+    }
+}
diff --git a/src/main/resources/applicationContext.xml b/src/main/resources/applicationContext.xml
deleted file mode 100755
index 2d33d8c..0000000
--- a/src/main/resources/applicationContext.xml
+++ /dev/null
@@ -1,22 +0,0 @@
-<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-       xmlns="http://www.springframework.org/schema/beans"
-       xmlns:aop="http://www.springframework.org/schema/aop"
-       xmlns:context="http://www.springframework.org/schema/context"
-       xmlns:jdbc="http://www.springframework.org/schema/jdbc"
-       xmlns:jee="http://www.springframework.org/schema/jee"
-       xmlns:tx="http://www.springframework.org/schema/tx"
-       xmlns:jpa="http://www.springframework.org/schema/data/jpa"
-       xsi:schemaLocation="
-       http://www.springframework.org/schema/aop          http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
-       http://www.springframework.org/schema/beans    http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
-       http://www.springframework.org/schema/context     http://www.springframework.org/schema/context/spring-context-3.2.xsd
-       http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.2.xsd
-       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
-       http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
-       http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
-       http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">
-
-  <context:annotation-config/>
-  <bean class="io.trygvis.spring.Config"/>
-
-</beans>
diff --git a/src/main/resources/create.sql b/src/main/resources/create-postgresql.sql
index f7f2939..39672f0 100644
--- a/src/main/resources/create.sql
+++ b/src/main/resources/create-postgresql.sql
@@ -2,7 +2,7 @@ BEGIN;
 
 DROP TABLE IF EXISTS task;
 DROP TABLE IF EXISTS queue;
-DROP SEQUENCE IF EXISTS task_id;
+DROP SEQUENCE IF EXISTS task_seq;
 
 CREATE TABLE queue (
   name     VARCHAR(100) NOT NULL,
@@ -12,7 +12,7 @@ CREATE TABLE queue (
 
 CREATE TABLE task (
   id        BIGINT       NOT NULL,
-  parent    BIGINT       NOT NULL,
+  parent    BIGINT,
   queue     VARCHAR(100) NOT NULL,
   scheduled TIMESTAMP    NOT NULL,
   last_run  TIMESTAMP,
@@ -24,6 +24,6 @@ CREATE TABLE task (
   CONSTRAINT fk_task__parent FOREIGN KEY (parent) REFERENCES task (id)
 );
 
-CREATE SEQUENCE task_id;
+CREATE SEQUENCE task_seq;
 
 COMMIT;