MAP_PICK
Introduced or updated: v1.2.654
Returns a new MAP containing the specified key-value pairs from an existing MAP.
Syntax
MAP_PICK( <map>, <key1> [, <key2>, ... ] )
MAP_PICK( <map>, <array> )
Arguments
| Arguments | Description |
|---|---|
<map> | The input MAP. |
<keyN> | The KEYs to be included from the returned MAP. |
<array> | The Array of KEYs to be included from the returned MAP. |
备注
- The types of the key expressions and the keys in the map must be the same.
- Key values not found in the map will be ignored.
Return Type
Map.
Examples
SELECT MAP_PICK({'a':1,'b':2,'c':3}, 'a', 'c');
┌─────────────────────────────────────────┐
│ map_pick({'a':1,'b':2,'c':3}, 'a', 'c') │
├─────────────────────────────────────────┤
│ {'a':1,'c':3} │
└─────────────────────────────────────────┘
SELECT MAP_PICK({'a':1,'b':2,'c':3}, ['a', 'b']);
┌───────────────────────────────────────────┐
│ map_pick({'a':1,'b':2,'c':3}, ['a', 'b']) │
├───────────────────────────────────────────┤
│ {'a':1,'b':2} │
└───────────────────────────────────────────┘