MAP_CONTAINS_KEY

Description

Determines whether a given map contains a specific key key

Syntax

MAP_CONTAINS_KEY(<map>, <key>)

Parameters

• <map> MAP type, the input map content.
• <key> Key type supported by MAP, the key to be searched.

Return Value

Determines whether a given map contains a specific key key, returns 1 if it exists, returns 0 if it does not exist.

Examples

select map_contains_key(map(null, 1, 2, null), null),map_contains_key(map(1, "100", 0.1, 2), 0.11);

+-----------------------------------------------+-----------------------------------------------+
| map_contains_key(map(null, 1, 2, null), null) | map_contains_key(map(1, "100", 0.1, 2), 0.11) |
+-----------------------------------------------+-----------------------------------------------+
|                                             1 |                                             0 |
+-----------------------------------------------+-----------------------------------------------+

Key comparison in Map uses "null-safe equal" (null and null are considered equal), which is different from

select map_contains_key(map(null,1), null);

+-------------------------------------+
| map_contains_key(map(null,1), null) |
+-------------------------------------+
|                                   1 |
+-------------------------------------+