Ejemplo n.º 1
0
        private string GetLoadingSelectStatement(ClassInfo classInfo, TableInfo tableInfo, out TableInfo[] loadedTables)
        {
            TableLoadingCache cache;

            if (tableLoadingCache.TryGetValue(tableInfo, out cache))
            {
                loadedTables = cache.LoadedTables;
                return(cache.SelectStatement);
            }

            Queue <_QueueItem> queue      = new Queue <_QueueItem>();
            List <TableInfo>   additional = new List <TableInfo>();

            additional.Add(tableInfo);

            SoqlQueryExpression queryExpression = new SoqlQueryExpression();

            queryExpression.From.Add(classInfo.Name);
            queryExpression.FromAliases.Add("");

            foreach (FieldInfo fi in tableInfo.Fields)
            {
                SoqlPathExpression pathExpr = new SoqlPathExpression(fi.Name);
                queryExpression.SelectExpressions.Add(pathExpr);
                queryExpression.SelectAliases.Add("");

                if (fi.ReferencedClass != null && fi.PrefetchLevel > 0)
                {
                    _QueueItem item = new _QueueItem();
                    item.classInfo = fi.ReferencedClass;
                    item.level     = fi.PrefetchLevel;
                    item.prefix    = pathExpr;
                    queue.Enqueue(item);
                }
            }

            // TODO - add prefetching
            while (queue.Count > 0)
            {
                _QueueItem it = queue.Dequeue();

                foreach (TableInfo ti in it.classInfo.UnifiedTables)
                {
                    additional.Add(ti);

                    foreach (FieldInfo fi in ti.Fields)
                    {
                        // TODO - this relies on the fact that path expressions
                        // are never reconstructed or broken. We simply share previous prefix
                        // perhaps it's cleaner to Clone() the expression here

                        SoqlPathExpression extendedExpression = new SoqlPathExpression(it.prefix, fi.Name);

                        queryExpression.SelectExpressions.Add(extendedExpression);
                        queryExpression.SelectAliases.Add("");

                        if (it.level >= 1 && fi.PrefetchLevel > 0 && fi.ReferencedClass != null)
                        {
                            _QueueItem newItem = new _QueueItem();
                            newItem.classInfo = fi.ReferencedClass;
                            newItem.prefix    = extendedExpression;
                            newItem.level     = it.level - 1;
                            queue.Enqueue(newItem);
                        }
                    }
                }
            }

            queryExpression.WhereClause = null;

            int parameterPos = 0;

            foreach (FieldInfo fi in tableInfo.Fields)
            {
                if (fi.IsPrimaryKey)
                {
                    SoqlBooleanRelationalExpression expr = Soql.FieldEqualsParam(fi.Name, parameterPos);

                    if (parameterPos == 0)
                    {
                        queryExpression.WhereClause = expr;
                    }
                    else
                    {
                        queryExpression.WhereClause = new SoqlBooleanAndExpression(queryExpression.WhereClause, expr);
                    }
                    parameterPos++;
                }
            }

            string query = SoqlToSql(queryExpression, tableInfo.OwnerClass.Schema, false);

            // logger.Debug("Loading statement for table {0}: {1}", tableInfo.NameToken, query);

            loadedTables = additional.ToArray();
            tableLoadingCache[tableInfo] = new TableLoadingCache(query, loadedTables);
            return(query);
        }
        protected override void LoadData()
        {
            SoodaDataSource ds = transaction.OpenDataSource(classInfo.GetDataSource());

            TableInfo[] loadedTables;

            items      = new Dictionary <SoodaObject, int>();
            itemsArray = new List <SoodaObject>();

            ISoodaObjectFactory factory     = transaction.GetFactory(classInfo);
            SoodaWhereClause    whereClause = new SoodaWhereClause(Soql.FieldEqualsParam(childRefField, 0), parentObject.GetPrimaryKeyValue());

            if (additionalWhereClause != null)
            {
                whereClause = whereClause.Append(additionalWhereClause);
            }

            string cacheKey = null;

            if (cached)
            {
                // cache makes sense only on clean database
                if (!transaction.HasBeenPrecommitted(classInfo.GetRootClass()))
                {
                    cacheKey = SoodaCache.GetCollectionKey(classInfo, whereClause);
                }
            }
            IEnumerable keysCollection = transaction.LoadCollectionFromCache(cacheKey, logger);

            if (keysCollection != null)
            {
                foreach (object o in keysCollection)
                {
                    SoodaObject obj = factory.GetRef(transaction, o);
                    // this binds to cache
                    obj.EnsureFieldsInited();

                    if (tempItems != null)
                    {
                        CollectionChange change;
                        if (tempItems.TryGetValue(obj, out change) && change == CollectionChange.Removed)
                        {
                            continue;
                        }
                    }

                    items.Add(obj, itemsArray.Count);
                    itemsArray.Add(obj);
                }
            }
            else
            {
                using (IDataReader reader = ds.LoadObjectList(transaction.Schema, classInfo, whereClause, null, 0, -1, SoodaSnapshotOptions.Default, out loadedTables))
                {
                    List <SoodaObject> readObjects = null;

                    if (cached)
                    {
                        readObjects = new List <SoodaObject>();
                    }

                    while (reader.Read())
                    {
                        SoodaObject obj = SoodaObject.GetRefFromRecordHelper(transaction, factory, reader, 0, loadedTables, 0);
                        if (readObjects != null)
                        {
                            readObjects.Add(obj);
                        }

                        if (tempItems != null)
                        {
                            CollectionChange change;
                            if (tempItems.TryGetValue(obj, out change) && change == CollectionChange.Removed)
                            {
                                continue;
                            }
                        }

                        items.Add(obj, itemsArray.Count);
                        itemsArray.Add(obj);
                    }
                    if (cached)
                    {
                        TimeSpan expirationTimeout;
                        bool     slidingExpiration;

                        if (transaction.CachingPolicy.GetExpirationTimeout(
                                classInfo, whereClause, null, 0, -1, readObjects.Count,
                                out expirationTimeout, out slidingExpiration))
                        {
                            transaction.StoreCollectionInCache(cacheKey, classInfo, readObjects, null, true, expirationTimeout, slidingExpiration);
                        }
                    }
                }
            }

            if (tempItems != null)
            {
                foreach (KeyValuePair <SoodaObject, CollectionChange> entry in tempItems)
                {
                    if (entry.Value == CollectionChange.Added)
                    {
                        SoodaObject obj = (SoodaObject)entry.Key;

                        if (!items.ContainsKey(obj))
                        {
                            items.Add(obj, itemsArray.Count);
                            itemsArray.Add(obj);
                        }
                    }
                }
            }
        }