Move app/sql/* files to sql/ directory.
I can't remove app/app.gyp and app/app_base.gypi yet because they are referenced
by third_party gyp files :(
BUG=72317
TEST=None
[email protected]
move app/sql to sql
Review URL: http://codereview.chromium.org/7353026
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@93069 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/sql/meta_table.h b/sql/meta_table.h
new file mode 100644
index 0000000..4a640d8
--- /dev/null
+++ b/sql/meta_table.h
@@ -0,0 +1,83 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SQL_META_TABLE_H_
+#define SQL_META_TABLE_H_
+#pragma once
+
+#include <string>
+
+#include "base/basictypes.h"
+
+namespace sql {
+
+class Connection;
+class Statement;
+
+class MetaTable {
+ public:
+ MetaTable();
+ ~MetaTable();
+
+ // Returns true if the 'meta' table exists.
+ static bool DoesTableExist(Connection* db);
+
+ // Initializes the MetaTableHelper, creating the meta table if necessary. For
+ // new tables, it will initialize the version number to |version| and the
+ // compatible version number to |compatible_version|.
+ bool Init(Connection* db, int version, int compatible_version);
+
+ // Resets this MetaTable object, making another call to Init() possible.
+ void Reset();
+
+ // The version number of the database. This should be the version number of
+ // the creator of the file. The version number will be 0 if there is no
+ // previously set version number.
+ //
+ // See also Get/SetCompatibleVersionNumber().
+ void SetVersionNumber(int version);
+ int GetVersionNumber();
+
+ // The compatible version number is the lowest version of the code that this
+ // database can be read by. If there are minor changes or additions, old
+ // versions of the code can still work with the database without failing.
+ //
+ // For example, if an optional column is added to a table in version 3, the
+ // new code will set the version to 3, and the compatible version to 2, since
+ // the code expecting version 2 databases can still read and write the table.
+ //
+ // Rule of thumb: check the version number when you're upgrading, but check
+ // the compatible version number to see if you can read the file at all. If
+ // it's larger than you code is expecting, fail.
+ //
+ // The compatible version number will be 0 if there is no previously set
+ // compatible version number.
+ void SetCompatibleVersionNumber(int version);
+ int GetCompatibleVersionNumber();
+
+ // Set the given arbitrary key with the given data. Returns true on success.
+ bool SetValue(const char* key, const std::string& value);
+ bool SetValue(const char* key, int value);
+ bool SetValue(const char* key, int64 value);
+
+ // Retrieves the value associated with the given key. This will use sqlite's
+ // type conversion rules. It will return true on success.
+ bool GetValue(const char* key, std::string* value);
+ bool GetValue(const char* key, int* value);
+ bool GetValue(const char* key, int64* value);
+
+ private:
+ // Conveniences to prepare the two types of statements used by
+ // MetaTableHelper.
+ bool PrepareSetStatement(Statement* statement, const char* key);
+ bool PrepareGetStatement(Statement* statement, const char* key);
+
+ Connection* db_;
+
+ DISALLOW_COPY_AND_ASSIGN(MetaTable);
+};
+
+} // namespace sql
+
+#endif // SQL_META_TABLE_H_
