MySQL JSON - using IN statement | json_contains

Question

I'm trying to select all columns where the roles property in the json column contains ANY of the values.

Statements I've tried:

SELECT * FROM components WHERE json->'$.roles' IN(1)

• this doesn't even work but it should in my opinion...

SELECT * FROM components WHERE JSON_CONTAINS(components, '1', '$.roles')

• this does work however is strict, so when I use 1 it pulls both like it should because they both contain 1, however if I insert 1,2 or JSON_ARRAY(1,2) it will only pull the later row because it isn't checking per array element...

I have the following table components structure and data:

+====+========================================================================================================================================================================================================+==+
| id |                                                                                                  json                                                                                                  |  |
+====+========================================================================================================================================================================================================+==+
|  1 | {"area": 1, "roles": [1], "elements": [{"home": {"content": "Home", "attributes": {"class": "my_class_1"}}}, {"dashboard": {"content": "Dashboard", "attributes": {"class": "my_class_1"}}}]}          |  |
+----+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--+
|  2 | {"area": 1, "roles": [1, 2, 5], "elements": [{"home": {"content": "Testing", "attributes": {"class": "my_class_1"}}}, {"dashboard": {"content": "Dashboard", "attributes": {"class": "my_class_1"}}}]} |  |
+----+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--+

Question: How can I modify either of these statements to allow them to query the rows based on the values in the roles property?

Answer 1

The expression

value in (x, y, z, ...)

is equivalent to

value = x OR value = y OR value = z OR ...

This doesn't work for an array like json->'$.roles' because an array is not equal to its elements, you need to call JSON_CONTAINS() to test that.

For what you want, you need to call JSON_CONTAINS() for each value you want to test.

WHERE JSON_CONTAINS(components, '1', '$.roles') OR JSON_CONTAINS(components, '2', '$.roles')

Answer 2

See https://dev.mysql.com/doc/refman/8.0/en/json-search-functions.html#function_json-overlaps

JSON_OVERLAPS(json_doc1, json_doc2)

Compares two JSON documents. Returns true (1) if the two document have any key-value pairs or array elements in common. If both arguments are scalars, the function performs a simple equality test.

This function serves as counterpart to JSON_CONTAINS(), which requires all elements of the array searched for to be present in the array searched in. Thus, JSON_CONTAINS() performs an AND operation on search keys, while JSON_OVERLAPS() performs an OR operation.

Queries on JSON columns of InnoDB tables using JSON_OVERLAPS() in the WHERE clause can be optimized using multi-valued indexes. Multi-Valued Indexes, provides detailed information and examples.

When comparing two arrays, JSON_OVERLAPS() returns true if they share one or more array elements in common, and false if they do not.

mysql> SELECT JSON_OVERLAPS("[1,3,5,7]", "[2,5,7]");
+---------------------------------------+
| JSON_OVERLAPS("[1,3,5,7]", "[2,5,7]") |
+---------------------------------------+
|                                     1 |
+---------------------------------------+
1 row in set (0.00 sec)

mysql> SELECT JSON_OVERLAPS("[1,3,5,7]", "[2,6,7]");
+---------------------------------------+
| JSON_OVERLAPS("[1,3,5,7]", "[2,6,7]") |
+---------------------------------------+
|                                     1 |
+---------------------------------------+
1 row in set (0.00 sec)

mysql> SELECT JSON_OVERLAPS("[1,3,5,7]", "[2,6,8]");
+---------------------------------------+
| JSON_OVERLAPS("[1,3,5,7]", "[2,6,8]") |
+---------------------------------------+
|                                     0 |
+---------------------------------------+
1 row in set (0.00 sec)

Answer 3

try one of these it should work

SELECT * FROM components WHERE JSON_CONTAINS([1],  roles, '$');

SELECT * FROM components WHERE JSON_CONTAINS([1],  CAST(roles as JSON), '$');

Answer 4

Just tried because i got a similar issue, and the following works for me:

field->'$.sub' REGEXP '^(1|3|5)$'

Yes, it seems that it is possible to use regular expressions here...

Note that if you try to query a string field in the json you should considder that strings are surrounded by a ", so you have to query something like this:

customer->'$.mail' REGEXP '^\"(info|contact)@.*\.com\"$'

Hope it helps, but i dont know how that impacts in performance...