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Updated on 2022-09-29 GMT+08:00

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Collection Functions

Description

**Table 1** Collection functions
Collection Functions	Description
CARDINALITY(array)	Returns the number of elements in array.
array '[' integer ']'	Returns the element at position INT in array. The index starts from 1.
ELEMENT(array)	Returns the sole element of array (whose cardinality should be one) Returns NULL if array is empty. Throws an exception if array has more than one element.
CARDINALITY(map)	Returns the number of entries in map.
map '[' key ']'	Returns the value specified by key value in map.

Parent topic: Built-In Functions

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