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A transaction represents a series of changes to the repository that must execute successfully and completely or not at all. Transactions are should be used to ensure consistency. Each transaction must succeed succeeds or fail fails as a complete unit; it cannot remain in an intermediate state.
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A string of characters used to identify a name of a web resource. It is defined in RFC3986, section 3 of http://tools. ietf.org/html/rfc3986#section-3. An example of a URI would be "http://purl.org/dc/elements/1.1/".
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A "practically" unique identifier that is used to identify a node. For more detailed description see wikipedia.
Version
A snapshot of a resource that is saved in version history for later access.
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