mirror of https://gitee.com/bigwinds/arangodb
29 lines
1.3 KiB
Plaintext
29 lines
1.3 KiB
Plaintext
!CHAPTER Document Keys
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Users can define their own keys for documents they save. The document key will
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be saved along with a document in the *_key* attribute. Users can pick key
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values as required, provided that the values conform to the following
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restrictions:
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* The key must be at least 1 byte and at most 254 bytes long. Empty keys are
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disallowed when specified (though it may be valid to completely omit the
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*_key* attribute from a document)
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* It must consist of the letters a-z (lower or upper case), the digits 0-9,
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the underscore (`_`), dash (`-`), colon (`:`), dot (.) or at-mark (`@`) characters
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only
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* Any other characters, especially multi-byte sequences, whitespace or punctuation
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characters cannot be used inside key values
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* The key must be unique within the collection it is used
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Keys are case-sensitive, i.e. *myKey* and *MyKEY* are considered to be
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different keys.
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Specifying a document key is optional when creating new documents. If no
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document key is specified by the user, ArangoDB will create the document key
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itself as each document is required to have a key.
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There are no guarantees about the format and pattern of auto-generated document
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keys other than the above restrictions. Clients should therefore treat
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auto-generated document keys as opaque values and not rely on their format.
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