We have been preparing our CMS installations for upgrading and basically replicating our production environment for testing purposes. One of the stumbling blocks we hit was exporting schema.
The CMS has two powerful applications for migrating schema... but which does what? Archiver is used primarily to export content while the Configuration Migration Utility (CMU) is a component that exports all sorts of configuration settings. Between the two you can fuddle your way through migration... but we hit a snag. How do we export schema?
Well, we started with CMU. It bundled up all our schema Tables and schema Views quite nicely... until we discovered they were empty of values!
It turns out CMU can't export values in a schema.
So we went back to Archiver and sure enough, it exports schema too, as tables. We found plenty of documentation about exporting table structures... but nothing about values! Anyway we dutifully added all our tables using the default Archiver settings and ran the export/import. Sure enough, all our tables were recreated... and empty!
Obviously this was extremely frustrating... but eventually we worked it out.
Archiver's default settings for exporting tables were the problem. Each time you select a table that contains timestamps, Archiver automatically selects the timestamps as criteria for deciding what values to export. This results in... no values! Make sure you deselect these criteria - they should all be empty.
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