element_at
Description
Returns the value for the specified key from a key-value pair of a map. If any input parameter is NULL or if the key does not exist in the map, the result is NULL.
If you want to retrieve an element from an array, see element_at.
This function is supported from v3.0 onwards.
Syntax
element_at(any_map, any_key)
Parameters
any_map
: a MAP expression from which to retrieve values.any_key
: a key in the map.
Return value
If any_key
exists in any_map
, the value corresponding to the key will be returned. Otherwise, NULL is returned.
Examples
mysql> select element_at(map{1:3,2:4},1);
+-----------------+
| map{1:3,2:4}[1] |
+-----------------+
| 3 |
+-----------------+
mysql> select element_at(map{1:3,2:4},3);
+-----------------+
| map{1:3,2:4}[3] |
+-----------------+
| NULL |
+-----------------+
mysql> select element_at(map{'a':1,'b':2},'a');
+-----------------------+
| map{'a':1,'b':2}['a'] |
+-----------------------+
| 1 |
+-----------------------+
keywords
ELEMENT_AT, MAP