| --- |
| { |
| "title": "ELEMENT_AT", |
| "language": "en" |
| } |
| --- |
| |
| ## element_at |
| |
| element_at |
| |
| ### description |
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| #### Syntax |
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| ```sql |
| T element_at(ARRAY<T> arr, BIGINT position) |
| T arr[position] |
| ``` |
| |
| Returns an element of an array located at the input position. If there is no element at the position, return NULL. |
| |
| `position` is 1-based and support negative number. |
| |
| ### example |
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| positive `position` example: |
| |
| ``` |
| mysql> SELECT id,c_array,element_at(c_array, 5) FROM `array_test`; |
| +------+-----------------+--------------------------+ |
| | id | c_array | element_at(`c_array`, 5) | |
| +------+-----------------+--------------------------+ |
| | 1 | [1, 2, 3, 4, 5] | 5 | |
| | 2 | [6, 7, 8] | NULL | |
| | 3 | [] | NULL | |
| | 4 | NULL | NULL | |
| +------+-----------------+--------------------------+ |
| ``` |
| |
| negative `position` example: |
| |
| ``` |
| mysql> SELECT id,c_array,c_array[-2] FROM `array_test`; |
| +------+-----------------+----------------------------------+ |
| | id | c_array | %element_extract%(`c_array`, -2) | |
| +------+-----------------+----------------------------------+ |
| | 1 | [1, 2, 3, 4, 5] | 4 | |
| | 2 | [6, 7, 8] | 7 | |
| | 3 | [] | NULL | |
| | 4 | NULL | NULL | |
| +------+-----------------+----------------------------------+ |
| ``` |
| |
| ### keywords |
| |
| ELEMENT_AT, SUBSCRIPT |
| |