private void testConcurrentTransactionsReadCommitted() {
MVStore s = MVStore.open(null);
TransactionStore ts = new TransactionStore(s);
Transaction tx1, tx2;
TransactionMap<String, String> m1, m2;
tx1 = ts.begin();
m1 = tx1.openMap("test");
m1.put("1", "Hi");
m1.put("3", ".");
tx1.commit();
tx1 = ts.begin();
m1 = tx1.openMap("test");
m1.put("1", "Hello");
m1.put("2", "World");
m1.remove("3");
tx1.commit();
// start new transaction to read old data
tx2 = ts.begin();
m2 = tx2.openMap("test");
// start transaction tx1, update/delete/add
tx1 = ts.begin();
m1 = tx1.openMap("test");
m1.put("1", "Hallo");
m1.remove("2");
m1.put("3", "!");
assertEquals("Hello", m2.get("1"));
assertEquals("World", m2.get("2"));
assertNull(m2.get("3"));
tx1.commit();
assertEquals("Hallo", m2.get("1"));
assertNull(m2.get("2"));
assertEquals("!", m2.get("3"));
tx1 = ts.begin();
m1 = tx1.openMap("test");
m1.put("2", "World");
assertNull(m2.get("2"));
assertFalse(m2.tryRemove("2"));
assertFalse(m2.tryPut("2", "Welt"));
tx2 = ts.begin();
m2 = tx2.openMap("test");
assertNull(m2.get("2"));
m1.remove("2");
assertNull(m2.get("2"));
tx1.commit();
tx1 = ts.begin();
m1 = tx1.openMap("test");
assertNull(m1.get("2"));
m1.put("2", "World");
m1.put("2", "Welt");
tx1.rollback();
tx1 = ts.begin();
m1 = tx1.openMap("test");
assertNull(m1.get("2"));
ts.close();
s.close();
}
private void testCompareWithPostgreSQL() throws Exception {
ArrayList<Statement> statements = New.arrayList();
ArrayList<Transaction> transactions = New.arrayList();
ArrayList<TransactionMap<Integer, String>> maps = New.arrayList();
int connectionCount = 3, opCount = 1000, rowCount = 10;
try {
Class.forName("org.postgresql.Driver");
for (int i = 0; i < connectionCount; i++) {
Connection conn = DriverManager.getConnection("jdbc:postgresql:test", "sa", "sa");
statements.add(conn.createStatement());
}
} catch (Exception e) {
// database not installed - ok
return;
}
statements.get(0).execute("drop table if exists test cascade");
statements.get(0).execute("create table test(id int primary key, name varchar(255))");
MVStore s = MVStore.open(null);
TransactionStore ts = new TransactionStore(s);
for (int i = 0; i < connectionCount; i++) {
Statement stat = statements.get(i);
// 100 ms to avoid blocking (the test is single threaded)
stat.execute("set statement_timeout to 100");
Connection c = stat.getConnection();
c.setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED);
c.setAutoCommit(false);
Transaction transaction = ts.begin();
transactions.add(transaction);
TransactionMap<Integer, String> map;
map = transaction.openMap("test");
maps.add(map);
}
StringBuilder buff = new StringBuilder();
Random r = new Random(1);
try {
for (int i = 0; i < opCount; i++) {
int connIndex = r.nextInt(connectionCount);
Statement stat = statements.get(connIndex);
Transaction transaction = transactions.get(connIndex);
TransactionMap<Integer, String> map = maps.get(connIndex);
if (transaction == null) {
transaction = ts.begin();
map = transaction.openMap("test");
transactions.set(connIndex, transaction);
maps.set(connIndex, map);
// read all data, to get a snapshot
ResultSet rs = stat.executeQuery("select * from test order by id");
buff.append(i).append(": [" + connIndex + "]=");
int size = 0;
while (rs.next()) {
buff.append(' ');
int k = rs.getInt(1);
String v = rs.getString(2);
buff.append(k).append(':').append(v);
assertEquals(v, map.get(k));
size++;
}
buff.append('\n');
if (size != map.sizeAsLong()) {
assertEquals(size, map.sizeAsLong());
}
}
int x = r.nextInt(rowCount);
int y = r.nextInt(rowCount);
buff.append(i).append(": [" + connIndex + "]: ");
ResultSet rs = null;
switch (r.nextInt(7)) {
case 0:
buff.append("commit");
stat.getConnection().commit();
transaction.commit();
transactions.set(connIndex, null);
break;
case 1:
buff.append("rollback");
stat.getConnection().rollback();
transaction.rollback();
transactions.set(connIndex, null);
break;
case 2:
// insert or update
String old = map.get(x);
if (old == null) {
buff.append("insert " + x + "=" + y);
if (map.tryPut(x, "" + y)) {
stat.execute("insert into test values(" + x + ", '" + y + "')");
} else {
buff.append(" -> row was locked");
// the statement would time out in PostgreSQL
// TODO test sometimes if timeout occurs
}
} else {
buff.append("update " + x + "=" + y + " (old:" + old + ")");
if (map.tryPut(x, "" + y)) {
int c = stat.executeUpdate("update test set name = '" + y + "' where id = " + x);
assertEquals(1, c);
} else {
buff.append(" -> row was locked");
// the statement would time out in PostgreSQL
// TODO test sometimes if timeout occurs
}
}
break;
case 3:
buff.append("delete " + x);
try {
int c = stat.executeUpdate("delete from test where id = " + x);
if (c == 1) {
map.remove(x);
} else {
assertNull(map.get(x));
}
} catch (SQLException e) {
assertTrue(map.get(x) != null);
assertFalse(map.tryRemove(x));
// PostgreSQL needs to rollback
buff.append(" -> rollback");
stat.getConnection().rollback();
transaction.rollback();
transactions.set(connIndex, null);
}
break;
case 4:
case 5:
case 6:
rs = stat.executeQuery("select * from test where id = " + x);
String expected = rs.next() ? rs.getString(2) : null;
buff.append("select " + x + "=" + expected);
assertEquals("i:" + i, expected, map.get(x));
break;
}
buff.append('\n');
}
} catch (Exception e) {
e.printStackTrace();
fail(buff.toString());
}
for (Statement stat : statements) {
stat.getConnection().close();
}
ts.close();
s.close();
}