Syntax:
column->>path

This is an improved, unquoting extraction operator. Whereas the ->
operator simply extracts a value, the ->> operator in addition unquotes
the extracted result. In other words, given a JSON column value column
and a path expression path (a string literal), the following three
expressions return the same value:

o JSON_UNQUOTE( JSON_EXTRACT(column, path) )

o JSON_UNQUOTE(column -> path)

o column->>path

The ->> operator can be used wherever JSON_UNQUOTE(JSON_EXTRACT())
would be allowed. This includes (but is not limited to) SELECT lists,
WHERE and HAVING clauses, and ORDER BY and GROUP BY clauses.

URL: https://dev.mysql.com/doc/refman/8.0/en/json-search-functions.html

