Pretend you have a JSON array of data that looks roughly like the
following.
mysql> insert into x(y) values('["a","b","c","d"]');
Query OK, 1 row affected (0.10 sec)
You could get all the values from that array using
$[*]
mysql> select y->"$[*]" from x;
+----------------------+
| y->"$[*]" |
+----------------------+
| ["a", "b", "c", "d"] |
+----------------------+
1 row in set (0.00 sec)
Or the individual members of the array with an index that starts
with zero.
mysql> select y->"$[0]" from x;
+-----------+
| y->"$[0]" |
+-----------+
| "a" |
+-----------+
1 row in set (0.00 sec)
But what about the times you want the last item in the array and
really do not want to loop through all the items? How about using …