private void copyData() {
if (table.isTemporary()) {
throw DbException.getUnsupportedException("TEMP TABLE");
}
Database db = session.getDatabase();
String baseName = table.getName();
String tempName = db.getTempTableName(baseName, session);
Column[] columns = table.getColumns();
ArrayList<Column> newColumns = New.arrayList();
Table newTable = cloneTableStructure(columns, db, tempName, newColumns);
try {
// check if a view would become invalid
// (because the column to drop is referenced or so)
checkViews(table, newTable);
} catch (DbException e) {
execute("DROP TABLE " + newTable.getName(), true);
throw DbException.get(ErrorCode.VIEW_IS_INVALID_2, e, getSQL(), e.getMessage());
}
String tableName = table.getName();
ArrayList<TableView> views = table.getViews();
if (views != null) {
views = New.arrayList(views);
for (TableView view : views) {
table.removeView(view);
}
}
execute("DROP TABLE " + table.getSQL() + " IGNORE", true);
db.renameSchemaObject(session, newTable, tableName);
for (DbObject child : newTable.getChildren()) {
if (child instanceof Sequence) {
continue;
}
String name = child.getName();
if (name == null || child.getCreateSQL() == null) {
continue;
}
if (name.startsWith(tempName + "_")) {
name = name.substring(tempName.length() + 1);
SchemaObject so = (SchemaObject) child;
if (so instanceof Constraint) {
if (so.getSchema().findConstraint(session, name) != null) {
name = so.getSchema().getUniqueConstraintName(session, newTable);
}
} else if (so instanceof Index) {
if (so.getSchema().findIndex(session, name) != null) {
name = so.getSchema().getUniqueIndexName(session, newTable, name);
}
}
db.renameSchemaObject(session, so, name);
}
}
if (views != null) {
for (TableView view : views) {
String sql = view.getCreateSQL(true, true);
execute(sql, true);
}
}
}
private void compactRewrite(ArrayList<BTreeChunk> old) {
HashSet<Integer> set = New.hashSet();
for (BTreeChunk c : old) {
set.add(c.id);
}
if (!map.rewrite(set)) {
return;
}
freeUnusedChunks();
commitAndSave();
}
/**
* Get all objects.
*
* @return a (possible empty) list of all objects
*/
public ArrayList<SchemaObject> getAll() {
ArrayList<SchemaObject> all = New.arrayList();
all.addAll(getMap(DbObjectType.TABLE_OR_VIEW).values());
all.addAll(getMap(DbObjectType.SEQUENCE).values());
all.addAll(getMap(DbObjectType.INDEX).values());
all.addAll(getMap(DbObjectType.TRIGGER).values());
all.addAll(getMap(DbObjectType.CONSTRAINT).values());
all.addAll(getMap(DbObjectType.CONSTANT).values());
all.addAll(getMap(DbObjectType.FUNCTION_ALIAS).values());
return all;
}
private void checkDefaultReferencesTable(Expression defaultExpression) {
if (defaultExpression == null) {
return;
}
HashSet<DbObject> dependencies = New.hashSet();
ExpressionVisitor visitor = ExpressionVisitor.getDependenciesVisitor(dependencies);
defaultExpression.isEverything(visitor);
if (dependencies.contains(table)) {
throw DbException.get(ErrorCode.COLUMN_IS_REFERENCED_1, defaultExpression.getSQL());
}
}
@Override
public void removeChildrenAndResources(ServerSession session) {
while (triggers != null && triggers.size() > 0) {
TriggerObject obj = (TriggerObject) triggers.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (constraints != null && constraints.size() > 0) {
Constraint obj = (Constraint) constraints.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
// There can be dependencies between tables e.g. using computed columns,
// so we might need to loop over them multiple times.
boolean runLoopAgain = false;
do {
runLoopAgain = false;
if (tablesAndViews != null) {
// Loop over a copy because the map is modified underneath us.
for (Table obj : New.arrayList(tablesAndViews.values())) {
// Check for null because multiple tables might be deleted
// in one go underneath us.
if (obj.getName() != null) {
if (database.getDependentTable(obj, obj) == null) {
database.removeSchemaObject(session, obj);
} else {
runLoopAgain = true;
}
}
}
}
} while (runLoopAgain);
while (indexes != null && indexes.size() > 0) {
Index obj = (Index) indexes.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (sequences != null && sequences.size() > 0) {
Sequence obj = (Sequence) sequences.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (constants != null && constants.size() > 0) {
Constant obj = (Constant) constants.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (functions != null && functions.size() > 0) {
FunctionAlias obj = (FunctionAlias) functions.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
owner = null;
super.removeChildrenAndResources(session);
}
private ArrayList<BTreeChunk> compactGetOldChunks(int targetFillRate, int write) {
if (lastChunk == null) {
// nothing to do
return null;
}
readAllChunks();
// calculate the fill rate
long maxLengthSum = 0;
long maxLengthLiveSum = 0;
long time = getTimeSinceCreation();
for (BTreeChunk c : chunks.values()) {
// ignore young chunks, because we don't optimize those
if (c.time + retentionTime > time) {
continue;
}
maxLengthSum += c.maxLen;
maxLengthLiveSum += c.maxLenLive;
}
if (maxLengthLiveSum < 0) {
// no old data
return null;
}
// the fill rate of all chunks combined
if (maxLengthSum <= 0) {
// avoid division by 0
maxLengthSum = 1;
}
int fillRate = (int) (100 * maxLengthLiveSum / maxLengthSum);
if (fillRate >= targetFillRate) {
return null;
}
// the 'old' list contains the chunks we want to free up
ArrayList<BTreeChunk> old = New.arrayList();
BTreeChunk last = chunks.get(lastChunk.id);
for (BTreeChunk c : chunks.values()) {
// only look at chunk older than the retention time
// (it's possible to compact chunks earlier, but right
// now we don't do that)
if (c.time + retentionTime > time) {
continue;
}
long age = last.version - c.version + 1;
c.collectPriority = (int) (c.getFillRate() * 1000 / age);
old.add(c);
}
if (old.size() == 0) {
return null;
}
// sort the list, so the first entry should be collected first
Collections.sort(
old,
new Comparator<BTreeChunk>() {
@Override
public int compare(BTreeChunk o1, BTreeChunk o2) {
int comp = new Integer(o1.collectPriority).compareTo(o2.collectPriority);
if (comp == 0) {
comp = new Long(o1.maxLenLive).compareTo(o2.maxLenLive);
}
return comp;
}
});
// find out up to were in the old list we need to move
long written = 0;
int chunkCount = 0;
BTreeChunk move = null;
for (BTreeChunk c : old) {
if (move != null) {
if (c.collectPriority > 0 && written > write) {
break;
}
}
written += c.maxLenLive;
chunkCount++;
move = c;
}
if (chunkCount < 1) {
return null;
}
// remove the chunks we want to keep from this list
boolean remove = false;
for (Iterator<BTreeChunk> it = old.iterator(); it.hasNext(); ) {
BTreeChunk c = it.next();
if (move == c) {
remove = true;
} else if (remove) {
it.remove();
}
}
return old;
}
/**
* Get all tables and views.
*
* @return a (possible empty) list of all objects
*/
public ArrayList<Table> getAllTablesAndViews() {
synchronized (database) {
return New.arrayList(tablesAndViews.values());
}
}
/**
* Get all objects of the given type.
*
* @param type the object type
* @return a (possible empty) list of all objects
*/
public ArrayList<SchemaObject> getAll(DbObjectType type) {
HashMap<String, SchemaObject> map = getMap(type);
return New.arrayList(map.values());
}
/** A schema as created by the SQL statement CREATE SCHEMA */
public class Schema extends DbObjectBase {
private User owner;
private final boolean system;
private final HashMap<String, Table> tablesAndViews;
private final HashMap<String, Index> indexes;
private final HashMap<String, Sequence> sequences;
private final HashMap<String, TriggerObject> triggers;
private final HashMap<String, Constraint> constraints;
private final HashMap<String, Constant> constants;
private final HashMap<String, FunctionAlias> functions;
private Map<String, String> replicationProperties;
private ReplicationPropertiesChangeListener replicationPropertiesChangeListener;
/**
* The set of returned unique names that are not yet stored. It is used to avoid returning the
* same unique name twice when multiple threads concurrently create objects.
*/
private final HashSet<String> temporaryUniqueNames = New.hashSet();
/**
* Create a new schema object.
*
* @param database the database
* @param id the object id
* @param schemaName the schema name
* @param owner the owner of the schema
* @param system if this is a system schema (such a schema can not be dropped)
*/
public Schema(Database database, int id, String schemaName, User owner, boolean system) {
super(database, id, schemaName, Trace.SCHEMA);
tablesAndViews = database.newStringMap();
indexes = database.newStringMap();
sequences = database.newStringMap();
triggers = database.newStringMap();
constraints = database.newStringMap();
constants = database.newStringMap();
functions = database.newStringMap();
this.owner = owner;
this.system = system;
}
@Override
public DbObjectType getType() {
return DbObjectType.SCHEMA;
}
public Map<String, String> getReplicationProperties() {
return replicationProperties;
}
public void setReplicationProperties(Map<String, String> replicationProperties) {
this.replicationProperties = replicationProperties;
if (replicationPropertiesChangeListener != null)
replicationPropertiesChangeListener.replicationPropertiesChanged(this);
}
public void setReplicationPropertiesChangeListener(ReplicationPropertiesChangeListener listener) {
replicationPropertiesChangeListener = listener;
}
public static interface ReplicationPropertiesChangeListener {
void replicationPropertiesChanged(Schema schema);
}
/**
* Check if this schema can be dropped. System schemas can not be dropped.
*
* @return true if it can be dropped
*/
public boolean canDrop() {
return !system;
}
@Override
public String getCreateSQL() {
if (system) {
return null;
}
StatementBuilder sql = new StatementBuilder();
sql.append("CREATE SCHEMA IF NOT EXISTS ")
.append(database.getSQL())
.append(getSQL())
.append(" AUTHORIZATION ")
.append(owner.getSQL());
if (replicationProperties != null && !replicationProperties.isEmpty()) {
sql.append(" WITH REPLICATION = (");
for (Map.Entry<String, String> e : replicationProperties.entrySet()) {
sql.appendExceptFirst(",");
sql.append('\'').append(e.getKey()).append("':'").append(e.getValue()).append('\'');
}
sql.append(')');
}
return sql.toString();
}
@Override
public void removeChildrenAndResources(ServerSession session) {
while (triggers != null && triggers.size() > 0) {
TriggerObject obj = (TriggerObject) triggers.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (constraints != null && constraints.size() > 0) {
Constraint obj = (Constraint) constraints.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
// There can be dependencies between tables e.g. using computed columns,
// so we might need to loop over them multiple times.
boolean runLoopAgain = false;
do {
runLoopAgain = false;
if (tablesAndViews != null) {
// Loop over a copy because the map is modified underneath us.
for (Table obj : New.arrayList(tablesAndViews.values())) {
// Check for null because multiple tables might be deleted
// in one go underneath us.
if (obj.getName() != null) {
if (database.getDependentTable(obj, obj) == null) {
database.removeSchemaObject(session, obj);
} else {
runLoopAgain = true;
}
}
}
}
} while (runLoopAgain);
while (indexes != null && indexes.size() > 0) {
Index obj = (Index) indexes.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (sequences != null && sequences.size() > 0) {
Sequence obj = (Sequence) sequences.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (constants != null && constants.size() > 0) {
Constant obj = (Constant) constants.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
while (functions != null && functions.size() > 0) {
FunctionAlias obj = (FunctionAlias) functions.values().toArray()[0];
database.removeSchemaObject(session, obj);
}
owner = null;
super.removeChildrenAndResources(session);
}
/**
* Get the owner of this schema.
*
* @return the owner
*/
public User getOwner() {
return owner;
}
@SuppressWarnings("unchecked")
private HashMap<String, SchemaObject> getMap(DbObjectType type) {
HashMap<String, ? extends SchemaObject> result;
switch (type) {
case TABLE_OR_VIEW:
result = tablesAndViews;
break;
case SEQUENCE:
result = sequences;
break;
case INDEX:
result = indexes;
break;
case TRIGGER:
result = triggers;
break;
case CONSTRAINT:
result = constraints;
break;
case CONSTANT:
result = constants;
break;
case FUNCTION_ALIAS:
result = functions;
break;
default:
throw DbException.throwInternalError("type=" + type);
}
return (HashMap<String, SchemaObject>) result;
}
/**
* Add an object to this schema. This method must not be called within CreateSchemaObject; use
* Database.addSchemaObject() instead
*
* @param obj the object to add
*/
public void add(SchemaObject obj) {
if (SysProperties.CHECK && obj.getSchema() != this) {
DbException.throwInternalError("wrong schema");
}
String name = obj.getName();
HashMap<String, SchemaObject> map = getMap(obj.getType());
if (SysProperties.CHECK && map.get(name) != null) {
DbException.throwInternalError("object already exists: " + name);
}
map.put(name, obj);
freeUniqueName(name);
}
/**
* Rename an object.
*
* @param obj the object to rename
* @param newName the new name
*/
public void rename(SchemaObject obj, String newName) {
DbObjectType type = obj.getType();
HashMap<String, SchemaObject> map = getMap(type);
if (SysProperties.CHECK) {
if (!map.containsKey(obj.getName())) {
DbException.throwInternalError("not found: " + obj.getName());
}
if (obj.getName().equals(newName) || map.containsKey(newName)) {
DbException.throwInternalError("object already exists: " + newName);
}
}
obj.checkRename();
map.remove(obj.getName());
freeUniqueName(obj.getName());
obj.rename(newName);
map.put(newName, obj);
freeUniqueName(newName);
}
/**
* Try to find a table or view with this name. This method returns null if no object with this
* name exists. Local temporary tables are also returned.
*
* @param session the session
* @param name the object name
* @return the object or null
*/
public Table findTableOrView(ServerSession session, String name) {
Table table = tablesAndViews.get(name);
if (table == null && session != null) {
table = session.findLocalTempTable(name);
}
return table;
}
/**
* Try to find an index with this name. This method returns null if no object with this name
* exists.
*
* @param session the session
* @param name the object name
* @return the object or null
*/
public Index findIndex(ServerSession session, String name) {
Index index = indexes.get(name);
if (index == null) {
index = session.findLocalTempTableIndex(name);
}
return index;
}
/**
* Try to find a trigger with this name. This method returns null if no object with this name
* exists.
*
* @param name the object name
* @return the object or null
*/
public TriggerObject findTrigger(String name) {
return triggers.get(name);
}
/**
* Try to find a sequence with this name. This method returns null if no object with this name
* exists.
*
* @param sequenceName the object name
* @return the object or null
*/
public Sequence findSequence(String sequenceName) {
return sequences.get(sequenceName);
}
/**
* Try to find a constraint with this name. This method returns null if no object with this name
* exists.
*
* @param session the session
* @param name the object name
* @return the object or null
*/
public Constraint findConstraint(ServerSession session, String name) {
Constraint constraint = constraints.get(name);
if (constraint == null) {
constraint = session.findLocalTempTableConstraint(name);
}
return constraint;
}
/**
* Try to find a user defined constant with this name. This method returns null if no object with
* this name exists.
*
* @param constantName the object name
* @return the object or null
*/
public Constant findConstant(String constantName) {
return constants.get(constantName);
}
/**
* Try to find a user defined function with this name. This method returns null if no object with
* this name exists.
*
* @param functionAlias the object name
* @return the object or null
*/
public FunctionAlias findFunction(String functionAlias) {
return functions.get(functionAlias);
}
/**
* Release a unique object name.
*
* @param name the object name
*/
public void freeUniqueName(String name) {
if (name != null) {
synchronized (temporaryUniqueNames) {
temporaryUniqueNames.remove(name);
}
}
}
private String getUniqueName(
DbObject obj, HashMap<String, ? extends SchemaObject> map, String prefix) {
String hash = Integer.toHexString(obj.getName().hashCode()).toUpperCase();
String name = null;
synchronized (temporaryUniqueNames) {
for (int i = 1, len = hash.length(); i < len; i++) {
name = prefix + hash.substring(0, i);
if (!map.containsKey(name) && !temporaryUniqueNames.contains(name)) {
break;
}
name = null;
}
if (name == null) {
prefix = prefix + hash + "_";
for (int i = 0; ; i++) {
name = prefix + i;
if (!map.containsKey(name) && !temporaryUniqueNames.contains(name)) {
break;
}
}
}
temporaryUniqueNames.add(name);
}
return name;
}
/**
* Create a unique constraint name.
*
* @param session the session
* @param table the constraint table
* @return the unique name
*/
public String getUniqueConstraintName(ServerSession session, Table table) {
HashMap<String, Constraint> tableConstraints;
if (table.isTemporary() && !table.isGlobalTemporary()) {
tableConstraints = session.getLocalTempTableConstraints();
} else {
tableConstraints = constraints;
}
return getUniqueName(table, tableConstraints, "CONSTRAINT_");
}
/**
* Create a unique index name.
*
* @param session the session
* @param table the indexed table
* @param prefix the index name prefix
* @return the unique name
*/
public String getUniqueIndexName(ServerSession session, Table table, String prefix) {
HashMap<String, Index> tableIndexes;
if (table.isTemporary() && !table.isGlobalTemporary()) {
tableIndexes = session.getLocalTempTableIndexes();
} else {
tableIndexes = indexes;
}
return getUniqueName(table, tableIndexes, prefix);
}
/**
* Get the table or view with the given name. Local temporary tables are also returned.
*
* @param session the session
* @param name the table or view name
* @return the table or view
* @throws DbException if no such object exists
*/
public Table getTableOrView(ServerSession session, String name) {
Table table = tablesAndViews.get(name);
if (table == null) {
if (session != null) {
table = session.findLocalTempTable(name);
}
if (table == null) {
throw DbException.get(ErrorCode.TABLE_OR_VIEW_NOT_FOUND_1, name);
}
}
return table;
}
/**
* Get the index with the given name.
*
* @param name the index name
* @return the index
* @throws DbException if no such object exists
*/
public Index getIndex(String name) {
Index index = indexes.get(name);
if (index == null) {
throw DbException.get(ErrorCode.INDEX_NOT_FOUND_1, name);
}
return index;
}
/**
* Get the constraint with the given name.
*
* @param name the constraint name
* @return the constraint
* @throws DbException if no such object exists
*/
public Constraint getConstraint(String name) {
Constraint constraint = constraints.get(name);
if (constraint == null) {
throw DbException.get(ErrorCode.CONSTRAINT_NOT_FOUND_1, name);
}
return constraint;
}
/**
* Get the user defined constant with the given name.
*
* @param constantName the constant name
* @return the constant
* @throws DbException if no such object exists
*/
public Constant getConstant(String constantName) {
Constant constant = constants.get(constantName);
if (constant == null) {
throw DbException.get(ErrorCode.CONSTANT_NOT_FOUND_1, constantName);
}
return constant;
}
/**
* Get the sequence with the given name.
*
* @param sequenceName the sequence name
* @return the sequence
* @throws DbException if no such object exists
*/
public Sequence getSequence(String sequenceName) {
Sequence sequence = sequences.get(sequenceName);
if (sequence == null) {
throw DbException.get(ErrorCode.SEQUENCE_NOT_FOUND_1, sequenceName);
}
return sequence;
}
/**
* Get all objects.
*
* @return a (possible empty) list of all objects
*/
public ArrayList<SchemaObject> getAll() {
ArrayList<SchemaObject> all = New.arrayList();
all.addAll(getMap(DbObjectType.TABLE_OR_VIEW).values());
all.addAll(getMap(DbObjectType.SEQUENCE).values());
all.addAll(getMap(DbObjectType.INDEX).values());
all.addAll(getMap(DbObjectType.TRIGGER).values());
all.addAll(getMap(DbObjectType.CONSTRAINT).values());
all.addAll(getMap(DbObjectType.CONSTANT).values());
all.addAll(getMap(DbObjectType.FUNCTION_ALIAS).values());
return all;
}
/**
* Get all objects of the given type.
*
* @param type the object type
* @return a (possible empty) list of all objects
*/
public ArrayList<SchemaObject> getAll(DbObjectType type) {
HashMap<String, SchemaObject> map = getMap(type);
return New.arrayList(map.values());
}
/**
* Get all tables and views.
*
* @return a (possible empty) list of all objects
*/
public ArrayList<Table> getAllTablesAndViews() {
synchronized (database) {
return New.arrayList(tablesAndViews.values());
}
}
/**
* Remove an object from this schema.
*
* @param obj the object to remove
*/
public void remove(SchemaObject obj) {
String objName = obj.getName();
HashMap<String, SchemaObject> map = getMap(obj.getType());
if (SysProperties.CHECK && !map.containsKey(objName)) {
DbException.throwInternalError("not found: " + objName);
}
map.remove(objName);
freeUniqueName(objName);
}
/**
* Add a table to the schema.
*
* @param data the create table information
* @return the created {@link Table} object
*/
public Table createTable(CreateTableData data) {
synchronized (database) {
if (!data.temporary || data.globalTemporary) {
database.lockMeta(data.session);
}
data.schema = this;
if (data.isMemoryTable()) data.storageEngineName = MemoryStorageEngine.NAME;
// 用默认的数据库参数
if (data.storageEngineName == null) {
data.storageEngineName = database.getDefaultStorageEngineName();
}
if (data.storageEngineName != null) {
StorageEngine engine = StorageEngineManager.getInstance().getEngine(data.storageEngineName);
if (engine == null) {
try {
engine = (StorageEngine) Utils.loadUserClass(data.storageEngineName).newInstance();
StorageEngineManager.getInstance().registerEngine(engine);
} catch (Exception e) {
throw DbException.convert(e);
}
}
if (engine instanceof TableFactory) {
return ((TableFactory) engine).createTable(data);
}
return new StandardTable(data, engine);
}
throw DbException.convert(new NullPointerException("table engine is null"));
}
}
}
/** A simple hash table with an optimization for the last recently used object. */
public class SmallMap {
private final HashMap<Integer, Object> map = New.hashMap();
private Object cache;
private int cacheId;
private int lastId;
private final int maxElements;
/**
* Create a map with the given maximum number of entries.
*
* @param maxElements the maximum number of entries
*/
public SmallMap(int maxElements) {
this.maxElements = maxElements;
}
/**
* Add an object to the map. If the size of the map is larger than twice the maximum size, objects
* with a low id are removed.
*
* @param id the object id
* @param o the object
* @return the id
*/
public int addObject(int id, Object o) {
if (map.size() > maxElements * 2) {
Iterator<Integer> it = map.keySet().iterator();
while (it.hasNext()) {
Integer k = it.next();
if (k.intValue() + maxElements < lastId) {
it.remove();
}
}
}
if (id > lastId) {
lastId = id;
}
map.put(id, o);
cacheId = id;
cache = o;
return id;
}
/**
* Remove an object from the map.
*
* @param id the id of the object to remove
*/
public void freeObject(int id) {
if (cacheId == id) {
cacheId = -1;
cache = null;
}
map.remove(id);
}
/**
* Get an object from the map if it is stored.
*
* @param id the id of the object
* @param ifAvailable only return it if available, otherwise return null
* @return the object or null
* @throws DbException if isAvailable is false and the object has not been found
*/
public Object getObject(int id, boolean ifAvailable) {
if (id == cacheId) {
return cache;
}
Object obj = map.get(id);
if (obj == null && !ifAvailable) {
throw DbException.get(ErrorCode.OBJECT_CLOSED);
}
return obj;
}
}
/**
* The engine contains a map of all open databases. It is also responsible for opening and creating
* new databases. This is a singleton class.
*/
public class DatabaseEngine implements SessionFactory {
private static final HashMap<String, Database> DATABASES = New.hashMap();
private static final DatabaseEngine INSTANCE = new DatabaseEngine();
private static String hostAndPort;
public static String getHostAndPort() {
return hostAndPort;
}
public static DatabaseEngine getInstance() {
return INSTANCE;
}
public static Collection<Database> getDatabases() {
return DATABASES.values();
}
public static synchronized void init(String host, int port) {
hostAndPort = host + ":" + port;
StorageEngineManager.initStorageEngines();
SQLEngineManager.initSQLEngines();
SystemDatabase.init();
for (String dbName : SystemDatabase.findAll())
DATABASES.put(dbName, new Database(INSTANCE, true));
}
private volatile long wrongPasswordDelay = SysProperties.DELAY_WRONG_PASSWORD_MIN;
protected DatabaseEngine() {}
public Database createDatabase(boolean persistent) {
return new Database(this, persistent);
}
/**
* Called after a database has been closed, to remove the object from the list of open databases.
*
* @param dbName the database name
*/
public synchronized void closeDatabase(String dbName) {
DATABASES.remove(dbName);
}
@Override
public synchronized Session createSession(ConnectionInfo ci) {
return createSessionAndValidate(ci);
}
private Session createSessionAndValidate(ConnectionInfo ci) {
try {
boolean ifExists = ci.getProperty("IFEXISTS", false);
Session session;
for (int i = 0; ; i++) {
session = createSession(ci, ifExists);
if (session != null) {
break;
}
// we found a database that is currently closing
// wait a bit to avoid a busy loop (the method is synchronized)
if (i > 60 * 1000) {
// retry at most 1 minute
throw DbException.get(
ErrorCode.DATABASE_ALREADY_OPEN_1,
"Waited for database closing longer than 1 minute");
}
try {
Thread.sleep(1);
} catch (InterruptedException e) {
// ignore
}
}
initSession(session, ci);
validateUserAndPassword(true);
return session;
} catch (DbException e) {
if (e.getErrorCode() == ErrorCode.WRONG_USER_OR_PASSWORD) {
validateUserAndPassword(false);
}
throw e;
}
}
private Session createSession(ConnectionInfo ci, boolean ifExists) {
String name = ci.getDatabaseName();
name = Database.parseDatabaseShortName(ci.getDbSettings(), name);
Database database;
boolean openNew = ci.getProperty("OPEN_NEW", false);
if (openNew) {
database = null;
} else {
database = DATABASES.get(name);
}
User user = null;
boolean opened = false;
if (database == null) {
if (ifExists && !SystemDatabase.exists(name)) {
throw DbException.get(ErrorCode.DATABASE_NOT_FOUND_1, name);
}
database = createDatabase(ci.isPersistent());
database.init(ci, name);
opened = true;
if (database.getAllUsers().isEmpty()) {
// users is the last thing we add, so if no user is around,
// the database is new (or not initialized correctly)
user = new User(database, database.allocateObjectId(), ci.getUserName(), false);
user.setAdmin(true);
user.setUserPasswordHash(ci.getUserPasswordHash());
database.setMasterUser(user);
}
DATABASES.put(name, database);
if (database.isPersistent())
SystemDatabase.addDatabase(database.getShortName(), database.getStorageEngineName());
} else {
if (!database.isInitialized()) database.init(ci, name);
}
synchronized (database) {
if (opened) {
// start the thread when already synchronizing on the database
// otherwise a deadlock can occur when the writer thread
// opens a new database (as in recovery testing)
database.opened();
}
if (database.isClosing()) {
return null;
}
if (user == null) {
if (database.validateFilePasswordHash(
ci.getProperty("CIPHER", null), ci.getFilePasswordHash())) {
user = database.findUser(ci.getUserName());
if (user != null) {
if (!user.validateUserPasswordHash(ci.getUserPasswordHash())) {
user = null;
}
}
}
if (opened && (user == null || !user.isAdmin())) {
// reset - because the user is not an admin, and has no
// right to listen to exceptions
database.setEventListener(null);
}
}
if (user == null) {
database.removeSession(null);
throw DbException.get(ErrorCode.WRONG_USER_OR_PASSWORD);
}
Session session = database.createSession(user);
session.setConnectionInfo(ci);
return session;
}
}
private void initSession(Session session, ConnectionInfo ci) {
boolean ignoreUnknownSetting = ci.getProperty("IGNORE_UNKNOWN_SETTINGS", false);
String init = ci.getProperty("INIT", null);
session.setAllowLiterals(true);
CommandInterface command;
for (String setting : ci.getKeys()) {
if (SetTypes.contains(setting)) {
String value = ci.getProperty(setting);
try {
command =
session.prepareCommandLocal(
"SET " + session.getDatabase().quoteIdentifier(setting) + " " + value);
command.executeUpdate();
} catch (DbException e) {
if (!ignoreUnknownSetting) {
session.close();
throw e;
}
}
}
}
if (init != null) {
try {
command = session.prepareCommand(init, Integer.MAX_VALUE);
command.executeUpdate();
} catch (DbException e) {
if (!ignoreUnknownSetting) {
session.close();
throw e;
}
}
}
session.setAllowLiterals(false);
session.commit(true);
}
/**
* This method is called after validating user name and password. If user name and password were
* correct, the sleep time is reset, otherwise this method waits some time (to make brute force /
* rainbow table attacks harder) and then throws a 'wrong user or password' exception. The delay
* is a bit randomized to protect against timing attacks. Also the delay doubles after each
* unsuccessful logins, to make brute force attacks harder.
*
* <p>There is only one exception message both for wrong user and for wrong password, to make it
* harder to get the list of user names. This method must only be called from one place, so it is
* not possible from the stack trace to see if the user name was wrong or the password.
*
* @param correct if the user name or the password was correct
* @throws DbException the exception 'wrong user or password'
*/
private void validateUserAndPassword(boolean correct) {
int min = SysProperties.DELAY_WRONG_PASSWORD_MIN;
if (correct) {
long delay = wrongPasswordDelay;
if (delay > min && delay > 0) {
// the first correct password must be blocked,
// otherwise parallel attacks are possible
synchronized (this) {
// delay up to the last delay
// an attacker can't know how long it will be
delay = MathUtils.secureRandomInt((int) delay);
try {
Thread.sleep(delay);
} catch (InterruptedException e) {
// ignore
}
wrongPasswordDelay = min;
}
}
} else {
// this method is not synchronized on the Engine, so that
// regular successful attempts are not blocked
synchronized (this) {
long delay = wrongPasswordDelay;
int max = SysProperties.DELAY_WRONG_PASSWORD_MAX;
if (max <= 0) {
max = Integer.MAX_VALUE;
}
wrongPasswordDelay += wrongPasswordDelay;
if (wrongPasswordDelay > max || wrongPasswordDelay < 0) {
wrongPasswordDelay = max;
}
if (min > 0) {
// a bit more to protect against timing attacks
delay += Math.abs(MathUtils.secureRandomLong() % 100);
try {
Thread.sleep(delay);
} catch (InterruptedException e) {
// ignore
}
}
throw DbException.get(ErrorCode.WRONG_USER_OR_PASSWORD);
}
}
}
}
private Table cloneTableStructure(
Column[] columns, Database db, String tempName, ArrayList<Column> newColumns) {
for (Column col : columns) {
newColumns.add(col.getClone());
}
if (type == CommandInterface.ALTER_TABLE_DROP_COLUMN) {
int position = oldColumn.getColumnId();
newColumns.remove(position);
} else if (type == CommandInterface.ALTER_TABLE_ADD_COLUMN) {
int position;
if (addBefore != null) {
position = table.getColumn(addBefore).getColumnId();
} else if (addAfter != null) {
position = table.getColumn(addAfter).getColumnId() + 1;
} else {
position = columns.length;
}
for (Column column : columnsToAdd) {
newColumns.add(position++, column);
}
} else if (type == CommandInterface.ALTER_TABLE_ALTER_COLUMN_CHANGE_TYPE) {
int position = oldColumn.getColumnId();
newColumns.remove(position);
newColumns.add(position, newColumn);
}
// create a table object in order to get the SQL statement
// can't just use this table, because most column objects are 'shared'
// with the old table
// still need a new id because using 0 would mean: the new table tries
// to use the rows of the table 0 (the meta table)
int id = db.allocateObjectId();
CreateTableData data = new CreateTableData();
data.tableName = tempName;
data.id = id;
data.columns = newColumns;
data.temporary = table.isTemporary();
data.persistData = table.isPersistData();
data.persistIndexes = table.isPersistIndexes();
data.isHidden = table.isHidden();
data.create = true;
data.session = session;
data.storageEngineName = table.getStorageEngineName();
Table newTable = getSchema().createTable(data);
newTable.setComment(table.getComment());
StringBuilder buff = new StringBuilder();
buff.append(newTable.getCreateSQL());
if (table.supportsAlterColumnWithCopyData()) {
StringBuilder columnList = new StringBuilder();
for (Column nc : newColumns) {
if (columnList.length() > 0) {
columnList.append(", ");
}
if (type == CommandInterface.ALTER_TABLE_ADD_COLUMN && columnsToAdd.contains(nc)) {
Expression def = (Expression) nc.getDefaultExpression();
columnList.append(def == null ? "NULL" : def.getSQL());
} else {
columnList.append(nc.getSQL());
}
}
buff.append(" AS SELECT ");
if (columnList.length() == 0) {
// special case: insert into test select * from
buff.append('*');
} else {
buff.append(columnList);
}
buff.append(" FROM ").append(table.getSQL());
}
String newTableSQL = buff.toString();
String newTableName = newTable.getName();
Schema newTableSchema = newTable.getSchema();
newTable.removeChildrenAndResources(session);
execute(newTableSQL, true);
newTable = newTableSchema.getTableOrView(session, newTableName);
ArrayList<String> triggers = New.arrayList();
for (DbObject child : table.getChildren()) {
if (child instanceof Sequence) {
continue;
} else if (child instanceof Index) {
Index idx = (Index) child;
if (idx.getIndexType().getBelongsToConstraint()) {
continue;
}
}
String createSQL = child.getCreateSQL();
if (createSQL == null) {
continue;
}
if (child instanceof TableView) {
continue;
} else if (child.getType() == DbObject.TABLE_OR_VIEW) {
DbException.throwInternalError();
}
String quotedName = Parser.quoteIdentifier(tempName + "_" + child.getName());
String sql = null;
if (child instanceof ConstraintReferential) {
ConstraintReferential r = (ConstraintReferential) child;
if (r.getTable() != table) {
sql = r.getCreateSQLForCopy(r.getTable(), newTable, quotedName, false);
}
}
if (sql == null) {
sql = child.getCreateSQLForCopy(newTable, quotedName);
}
if (sql != null) {
if (child instanceof TriggerObject) {
triggers.add(sql);
} else {
execute(sql, true);
}
}
}
table.setModified();
// remove the sequences from the columns (except dropped columns)
// otherwise the sequence is dropped if the table is dropped
for (Column col : newColumns) {
Sequence seq = col.getSequence();
if (seq != null) {
table.removeSequence(seq);
col.setSequence(null);
}
}
for (String sql : triggers) {
execute(sql, true);
}
return newTable;
}
@Override
public int update() {
if (!transactional) {
session.commit(true);
}
Database db = session.getDatabase();
if (!db.isPersistent()) {
data.persistIndexes = false;
}
if (getSchema().findTableOrView(session, data.tableName) != null) {
if (ifNotExists) {
return 0;
}
throw DbException.get(ErrorCode.TABLE_OR_VIEW_ALREADY_EXISTS_1, data.tableName);
}
if (asQuery != null) {
asQuery.prepare();
if (data.columns.isEmpty()) {
generateColumnsFromQuery();
} else if (data.columns.size() != asQuery.getColumnCount()) {
throw DbException.get(ErrorCode.COLUMN_COUNT_DOES_NOT_MATCH);
}
}
if (pkColumns != null) {
for (Column c : data.columns) {
for (IndexColumn idxCol : pkColumns) {
if (c.getName().equals(idxCol.columnName)) {
c.setNullable(false);
}
}
}
}
data.id = getObjectId();
data.create = create;
data.session = session;
boolean isSessionTemporary = data.temporary && !data.globalTemporary;
if (!isSessionTemporary) {
db.lockMeta(session);
}
Table table = createTable(data);
ArrayList<Sequence> sequences = New.arrayList();
for (Column c : data.columns) {
if (c.isAutoIncrement()) {
int objId = getObjectId();
c.convertAutoIncrementToSequence(session, getSchema(), objId, data.temporary);
}
Sequence seq = c.getSequence();
if (seq != null) {
sequences.add(seq);
}
}
table.setComment(comment);
if (isSessionTemporary) {
if (onCommitDrop) {
table.setOnCommitDrop(true);
}
if (onCommitTruncate) {
table.setOnCommitTruncate(true);
}
session.addLocalTempTable(table);
} else {
db.lockMeta(session);
db.addSchemaObject(session, table);
}
try {
for (Column c : data.columns) {
c.prepareExpression(session);
}
for (Sequence sequence : sequences) {
table.addSequence(sequence);
}
for (DefineCommand command : constraintCommands) {
command.setTransactional(transactional);
command.update();
}
if (asQuery != null) {
Insert insert = null;
insert = new Insert(session);
insert.setSortedInsertMode(sortedInsertMode);
insert.setQuery(asQuery);
insert.setTable(table);
insert.setInsertFromSelect(true);
insert.prepare();
insert.update();
}
} catch (DbException e) {
db.checkPowerOff();
db.removeSchemaObject(session, table);
if (!transactional) {
session.commit(true);
}
throw e;
}
return 0;
}
/** This class represents the statement CREATE TABLE */
public class CreateTable extends SchemaCommand {
protected final CreateTableData data = new CreateTableData();
protected IndexColumn[] pkColumns;
protected boolean ifNotExists;
private final ArrayList<DefineCommand> constraintCommands = New.arrayList();
private boolean onCommitDrop;
private boolean onCommitTruncate;
private Query asQuery;
private String comment;
private boolean sortedInsertMode;
public CreateTable(Session session, Schema schema) {
super(session, schema);
data.persistIndexes = true;
data.persistData = true;
}
public void setQuery(Query query) {
this.asQuery = query;
}
public void setTemporary(boolean temporary) {
data.temporary = temporary;
}
public void setTableName(String tableName) {
data.tableName = tableName;
}
/**
* Add a column to this table.
*
* @param column the column to add
*/
public void addColumn(Column column) {
data.columns.add(column);
}
/**
* Add a constraint statement to this statement. The primary key definition is one possible
* constraint statement.
*
* @param command the statement to add
*/
public void addConstraintCommand(DefineCommand command) {
if (command instanceof CreateIndex) {
constraintCommands.add(command);
} else {
AlterTableAddConstraint con = (AlterTableAddConstraint) command;
boolean alreadySet;
if (con.getType() == CommandInterface.ALTER_TABLE_ADD_CONSTRAINT_PRIMARY_KEY) {
alreadySet = setPrimaryKeyColumns(con.getIndexColumns());
} else {
alreadySet = false;
}
if (!alreadySet) {
constraintCommands.add(command);
}
}
}
public void setIfNotExists(boolean ifNotExists) {
this.ifNotExists = ifNotExists;
}
@Override
public int update() {
if (!transactional) {
session.commit(true);
}
Database db = session.getDatabase();
if (!db.isPersistent()) {
data.persistIndexes = false;
}
if (getSchema().findTableOrView(session, data.tableName) != null) {
if (ifNotExists) {
return 0;
}
throw DbException.get(ErrorCode.TABLE_OR_VIEW_ALREADY_EXISTS_1, data.tableName);
}
if (asQuery != null) {
asQuery.prepare();
if (data.columns.isEmpty()) {
generateColumnsFromQuery();
} else if (data.columns.size() != asQuery.getColumnCount()) {
throw DbException.get(ErrorCode.COLUMN_COUNT_DOES_NOT_MATCH);
}
}
if (pkColumns != null) {
for (Column c : data.columns) {
for (IndexColumn idxCol : pkColumns) {
if (c.getName().equals(idxCol.columnName)) {
c.setNullable(false);
}
}
}
}
data.id = getObjectId();
data.create = create;
data.session = session;
boolean isSessionTemporary = data.temporary && !data.globalTemporary;
if (!isSessionTemporary) {
db.lockMeta(session);
}
Table table = createTable(data);
ArrayList<Sequence> sequences = New.arrayList();
for (Column c : data.columns) {
if (c.isAutoIncrement()) {
int objId = getObjectId();
c.convertAutoIncrementToSequence(session, getSchema(), objId, data.temporary);
}
Sequence seq = c.getSequence();
if (seq != null) {
sequences.add(seq);
}
}
table.setComment(comment);
if (isSessionTemporary) {
if (onCommitDrop) {
table.setOnCommitDrop(true);
}
if (onCommitTruncate) {
table.setOnCommitTruncate(true);
}
session.addLocalTempTable(table);
} else {
db.lockMeta(session);
db.addSchemaObject(session, table);
}
try {
for (Column c : data.columns) {
c.prepareExpression(session);
}
for (Sequence sequence : sequences) {
table.addSequence(sequence);
}
for (DefineCommand command : constraintCommands) {
command.setTransactional(transactional);
command.update();
}
if (asQuery != null) {
Insert insert = null;
insert = new Insert(session);
insert.setSortedInsertMode(sortedInsertMode);
insert.setQuery(asQuery);
insert.setTable(table);
insert.setInsertFromSelect(true);
insert.prepare();
insert.update();
}
} catch (DbException e) {
db.checkPowerOff();
db.removeSchemaObject(session, table);
if (!transactional) {
session.commit(true);
}
throw e;
}
return 0;
}
protected Table createTable(CreateTableData data) {
return getSchema().createTable(data);
}
private void generateColumnsFromQuery() {
int columnCount = asQuery.getColumnCount();
ArrayList<Expression> expressions = asQuery.getExpressions();
for (int i = 0; i < columnCount; i++) {
Expression expr = expressions.get(i);
int type = expr.getType();
String name = expr.getAlias();
long precision = expr.getPrecision();
int displaySize = expr.getDisplaySize();
DataType dt = DataType.getDataType(type);
if (precision > 0
&& (dt.defaultPrecision == 0
|| (dt.defaultPrecision > precision && dt.defaultPrecision < Byte.MAX_VALUE))) {
// dont' set precision to MAX_VALUE if this is the default
precision = dt.defaultPrecision;
}
int scale = expr.getScale();
if (scale > 0
&& (dt.defaultScale == 0 || (dt.defaultScale > scale && dt.defaultScale < precision))) {
scale = dt.defaultScale;
}
if (scale > precision) {
precision = scale;
}
Column col = new Column(name, type, precision, scale, displaySize);
addColumn(col);
}
}
/**
* Sets the primary key columns, but also check if a primary key with different columns is already
* defined.
*
* @param columns the primary key columns
* @return true if the same primary key columns where already set
*/
private boolean setPrimaryKeyColumns(IndexColumn[] columns) {
if (pkColumns != null) {
int len = columns.length;
if (len != pkColumns.length) {
throw DbException.get(ErrorCode.SECOND_PRIMARY_KEY);
}
for (int i = 0; i < len; i++) {
if (!columns[i].columnName.equals(pkColumns[i].columnName)) {
throw DbException.get(ErrorCode.SECOND_PRIMARY_KEY);
}
}
return true;
}
this.pkColumns = columns;
return false;
}
public void setPersistIndexes(boolean persistIndexes) {
data.persistIndexes = persistIndexes;
}
public void setGlobalTemporary(boolean globalTemporary) {
data.globalTemporary = globalTemporary;
}
/** This temporary table is dropped on commit. */
public void setOnCommitDrop() {
this.onCommitDrop = true;
}
/** This temporary table is truncated on commit. */
public void setOnCommitTruncate() {
this.onCommitTruncate = true;
}
public void setComment(String comment) {
this.comment = comment;
}
public void setPersistData(boolean persistData) {
data.persistData = persistData;
if (!persistData) {
data.persistIndexes = false;
}
}
public void setSortedInsertMode(boolean sortedInsertMode) {
this.sortedInsertMode = sortedInsertMode;
}
public void setStorageEngine(String storageEngine) {
data.storageEngine = storageEngine;
}
public void setHidden(boolean isHidden) {
data.isHidden = isHidden;
}
@Override
public int getType() {
return CommandInterface.CREATE_TABLE;
}
}