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+The Tianmu engine needs an upgrade tools, which provides some tools for 
+upgrade Tianmu from an old version to a new version. 
+The new version maybe changes the format of meta-data or format of data. 
+These format change will lead the new version of StoneDB can read the old-format data. 
+Therefore, StoneDB should provide an upgrading solution.
+
+All our information about Tianmu upgrading is in this directory.
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