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diff --git a/Source/WebCore/Modules/webdatabase/SQLStatementBackend.cpp b/Source/WebCore/Modules/webdatabase/SQLStatementBackend.cpp
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+/*
+ * Copyright (C) 2007, 2013 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "config.h"
+#include "SQLStatementBackend.h"
+
+#if ENABLE(SQL_DATABASE)
+
+#include "AbstractSQLStatement.h"
+#include "DatabaseBackend.h"
+#include "Logging.h"
+#include "SQLError.h"
+#include "SQLValue.h"
+#include "SQLiteDatabase.h"
+#include "SQLiteStatement.h"
+#include <wtf/text/CString.h>
+
+
+// The Life-Cycle of a SQLStatement i.e. Who's keeping the SQLStatement alive? 
+// ==========================================================================
+// The RefPtr chain goes something like this:
+//
+//     At birth (in SQLTransactionBackend::executeSQL()):
+//     =================================================
+//     SQLTransactionBackend           // Deque<RefPtr<SQLStatementBackend>> m_statementQueue points to ...
+//     --> SQLStatementBackend         // OwnPtr<SQLStatement> m_frontend points to ...
+//         --> SQLStatement
+//
+//     After grabbing the statement for execution (in SQLTransactionBackend::getNextStatement()):
+//     =========================================================================================
+//     SQLTransactionBackend           // RefPtr<SQLStatementBackend> m_currentStatementBackend points to ...
+//     --> SQLStatementBackend         // OwnPtr<SQLStatement> m_frontend points to ...
+//         --> SQLStatement
+//
+//     Then we execute the statement in SQLTransactionBackend::runCurrentStatementAndGetNextState().
+//     And we callback to the script in SQLTransaction::deliverStatementCallback() if
+//     necessary.
+//     - Inside SQLTransaction::deliverStatementCallback(), we operate on a raw SQLStatement*.
+//       This pointer is valid because it is owned by SQLTransactionBackend's
+//       SQLTransactionBackend::m_currentStatementBackend.
+//
+//     After we're done executing the statement (in SQLTransactionBackend::getNextStatement()):
+//     =======================================================================================
+//     When we're done executing, we'll grab the next statement. But before we
+//     do that, getNextStatement() nullify SQLTransactionBackend::m_currentStatementBackend.
+//     This will trigger the deletion of the SQLStatementBackend and SQLStatement.
+//
+//     Note: unlike with SQLTransaction, there is no JS representation of SQLStatement.
+//     Hence, there is no GC dependency at play here.
+
+namespace WebCore {
+
+PassRefPtr<SQLStatementBackend> SQLStatementBackend::create(PassOwnPtr<AbstractSQLStatement> frontend,
+    const String& statement, const Vector<SQLValue>& arguments, int permissions)
+{
+    return adoptRef(new SQLStatementBackend(frontend, statement, arguments, permissions));
+}
+
+SQLStatementBackend::SQLStatementBackend(PassOwnPtr<AbstractSQLStatement> frontend,
+    const String& statement, const Vector<SQLValue>& arguments, int permissions)
+    : m_frontend(frontend)
+    , m_statement(statement.isolatedCopy())
+    , m_arguments(arguments)
+    , m_hasCallback(m_frontend->hasCallback())
+    , m_hasErrorCallback(m_frontend->hasErrorCallback())
+    , m_permissions(permissions)
+{
+    m_frontend->setBackend(this);
+}
+
+AbstractSQLStatement* SQLStatementBackend::frontend()
+{
+    return m_frontend.get();
+}
+
+PassRefPtr<SQLError> SQLStatementBackend::sqlError() const
+{
+    return m_error;
+}
+
+PassRefPtr<SQLResultSet> SQLStatementBackend::sqlResultSet() const
+{
+    return m_resultSet;
+}
+
+bool SQLStatementBackend::execute(DatabaseBackend* db)
+{
+    ASSERT(!m_resultSet);
+
+    // If we're re-running this statement after a quota violation, we need to clear that error now
+    clearFailureDueToQuota();
+
+    // This transaction might have been marked bad while it was being set up on the main thread,
+    // so if there is still an error, return false.
+    if (m_error)
+        return false;
+
+    db->setAuthorizerPermissions(m_permissions);
+
+    SQLiteDatabase* database = &db->sqliteDatabase();
+
+    SQLiteStatement statement(*database, m_statement);
+    int result = statement.prepare();
+
+    if (result != SQLResultOk) {
+        LOG(StorageAPI, "Unable to verify correctness of statement %s - error %i (%s)", m_statement.ascii().data(), result, database->lastErrorMsg());
+        if (result == SQLResultInterrupt)
+            m_error = SQLError::create(SQLError::DATABASE_ERR, "could not prepare statement", result, "interrupted");
+        else
+            m_error = SQLError::create(SQLError::SYNTAX_ERR, "could not prepare statement", result, database->lastErrorMsg());
+        return false;
+    }
+
+    // FIXME: If the statement uses the ?### syntax supported by sqlite, the bind parameter count is very likely off from the number of question marks.
+    // If this is the case, they might be trying to do something fishy or malicious
+    if (statement.bindParameterCount() != m_arguments.size()) {
+        LOG(StorageAPI, "Bind parameter count doesn't match number of question marks");
+        m_error = SQLError::create(db->isInterrupted() ? SQLError::DATABASE_ERR : SQLError::SYNTAX_ERR, "number of '?'s in statement string does not match argument count");
+        return false;
+    }
+
+    for (unsigned i = 0; i < m_arguments.size(); ++i) {
+        result = statement.bindValue(i + 1, m_arguments[i]);
+        if (result == SQLResultFull) {
+            setFailureDueToQuota();
+            return false;
+        }
+
+        if (result != SQLResultOk) {
+            LOG(StorageAPI, "Failed to bind value index %i to statement for query '%s'", i + 1, m_statement.ascii().data());
+            m_error = SQLError::create(SQLError::DATABASE_ERR, "could not bind value", result, database->lastErrorMsg());
+            return false;
+        }
+    }
+
+    RefPtr<SQLResultSet> resultSet = SQLResultSet::create();
+
+    // Step so we can fetch the column names.
+    result = statement.step();
+    if (result == SQLResultRow) {
+        int columnCount = statement.columnCount();
+        SQLResultSetRowList* rows = resultSet->rows();
+
+        for (int i = 0; i < columnCount; i++)
+            rows->addColumn(statement.getColumnName(i));
+
+        do {
+            for (int i = 0; i < columnCount; i++)
+                rows->addResult(statement.getColumnValue(i));
+
+            result = statement.step();
+        } while (result == SQLResultRow);
+
+        if (result != SQLResultDone) {
+            m_error = SQLError::create(SQLError::DATABASE_ERR, "could not iterate results", result, database->lastErrorMsg());
+            return false;
+        }
+    } else if (result == SQLResultDone) {
+        // Didn't find anything, or was an insert
+        if (db->lastActionWasInsert())
+            resultSet->setInsertId(database->lastInsertRowID());
+    } else if (result == SQLResultFull) {
+        // Return the Quota error - the delegate will be asked for more space and this statement might be re-run
+        setFailureDueToQuota();
+        return false;
+    } else if (result == SQLResultConstraint) {
+        m_error = SQLError::create(SQLError::CONSTRAINT_ERR, "could not execute statement due to a constaint failure", result, database->lastErrorMsg());
+        return false;
+    } else {
+        m_error = SQLError::create(SQLError::DATABASE_ERR, "could not execute statement", result, database->lastErrorMsg());
+        return false;
+    }
+
+    // FIXME: If the spec allows triggers, and we want to be "accurate" in a different way, we'd use
+    // sqlite3_total_changes() here instead of sqlite3_changed, because that includes rows modified from within a trigger
+    // For now, this seems sufficient
+    resultSet->setRowsAffected(database->lastChanges());
+
+    m_resultSet = resultSet;
+    return true;
+}
+
+void SQLStatementBackend::setDatabaseDeletedError()
+{
+    ASSERT(!m_error && !m_resultSet);
+    m_error = SQLError::create(SQLError::UNKNOWN_ERR, "unable to execute statement, because the user deleted the database");
+}
+
+void SQLStatementBackend::setVersionMismatchedError()
+{
+    ASSERT(!m_error && !m_resultSet);
+    m_error = SQLError::create(SQLError::VERSION_ERR, "current version of the database and `oldVersion` argument do not match");
+}
+
+void SQLStatementBackend::setFailureDueToQuota()
+{
+    ASSERT(!m_error && !m_resultSet);
+    m_error = SQLError::create(SQLError::QUOTA_ERR, "there was not enough remaining storage space, or the storage quota was reached and the user declined to allow more space");
+}
+
+void SQLStatementBackend::clearFailureDueToQuota()
+{
+    if (lastExecutionFailedDueToQuota())
+        m_error = 0;
+}
+
+bool SQLStatementBackend::lastExecutionFailedDueToQuota() const
+{
+    return m_error && m_error->code() == SQLError::QUOTA_ERR;
+}
+
+} // namespace WebCore
+
+#endif // ENABLE(SQL_DATABASE)