mirror of https://gitee.com/bigwinds/arangodb
28 lines
927 B
Markdown
28 lines
927 B
Markdown
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@brief checks whether a document exists
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`collection.exists(document)`
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The *exists* method determines whether a document exists given its
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identifier. Instead of returning the found document or an error, this
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method will return either *true* or *false*. It can thus be used
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for easy existence checks.
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The *document* method finds a document given its identifier. It returns
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the document. Note that the returned document contains two
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pseudo-attributes, namely *_id* and *_rev*. *_id* contains the
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document-handle and *_rev* the revision of the document.
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No error will be thrown if the sought document or collection does not
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exist.
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Still this method will throw an error if used improperly, e.g. when called
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with a non-document handle, a non-document, or when a cross-collection
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request is performed.
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`collection.exists(document-handle)`
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As before. Instead of document a *document-handle* can be passed as
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first argument.
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