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48 lines
1.5 KiB
Markdown
48 lines
1.5 KiB
Markdown
<a name="ext_dict_functions"></a>
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# Functions for working with external dictionaries
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For information on connecting and configuring external dictionaries, see "[External dictionaries](../dicts/external_dicts.md#dicts-external_dicts)".
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## dictGetUInt8, dictGetUInt16, dictGetUInt32, dictGetUInt64
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## dictGetInt8, dictGetInt16, dictGetInt32, dictGetInt64
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## dictGetFloat32, dictGetFloat64
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## dictGetDate, dictGetDateTime
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## dictGetUUID
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## dictGetString
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`dictGetT('dict_name', 'attr_name', id)`
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- Get the value of the attr_name attribute from the dict_name dictionary using the 'id' key.`dict_name` and `attr_name` are constant strings.`id`must be UInt64.
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If there is no `id` key in the dictionary, it returns the default value specified in the dictionary description.
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## dictGetTOrDefault
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`dictGetT('dict_name', 'attr_name', id, default)`
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Similar to the functions dictGetT, but the default value is taken from the last argument of the function.
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## dictIsIn
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`dictIsIn ('dict_name', child_id, ancestor_id)`
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- For the 'dict_name' hierarchical dictionary, finds out whether the 'child_id' key is located inside 'ancestor_id' (or matches 'ancestor_id'). Returns UInt8.
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## dictGetHierarchy
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`dictGetHierarchy('dict_name', id)`
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- For the 'dict_name' hierarchical dictionary, returns an array of dictionary keys starting from 'id' and continuing along the chain of parent elements. Returns Array(UInt64).
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## dictHas
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`dictHas('dict_name', id)`
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- Check whether the dictionary has the key. Returns a UInt8 value equal to 0 if there is no key and 1 if there is a key.
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