MySQL Parse and Split JSON value - mysql

Question

I have a column which contains a JSON value of different lengths
["The Cherries:2.50","Draw:3.25","Swansea Jacks:2.87"]
I want to split them and store into a JSON like so:
[
{
name: "The Cherries",
odds: 2.50
},
{
name: "Draw",
odds: 3.25
},
{
name: "Swansea",
odds: 2.87
},
]
What I did right now is looping and splitting them in the UI which to me is quite heavy for the client. I want to parse and split them all in a single query.

Answer 1

If you are running MySQL 8.0, you can use json_table() to split the original arrayto rows, and then build new objects and aggregate them with json_arrayagg().
We need a primary key column (or set of columns) so we can properly aggreate the generated rows, I assumed id:
select
t.id,
json_arrayagg(json_object(
'name', substring(j.val, 1, locate(':', j.val) - 1),
'odds', substring(j.val, locate(':', j.val) + 1)
)) new_js
from mytable t
cross join json_table(t.js, '$[*]' columns (val varchar(500) path '$')) as j
group by t.id
Demo on DB Fiddle
Sample data:
id | js
-: | :-------------------------------------------------------
1 | ["The Cherries:2.50", "Draw:3.25", "Swansea Jacks:2.87"]
Query results:
id | new_js
-: | :----------------------------------------------------------------------------------------------------------------------
1 | [{"name": "The Cherries", "odds": "2.50"}, {"name": "Draw", "odds": "3.25"}, {"name": "Swansea Jacks", "odds": "2.87"}]

Answer 2

You can use json_table to create rows from the json object.
Just replace table_name with your table name and json with the column that contains json
SELECT json_arrayagg(json_object('name',SUBSTRING_INDEX(person, ':', 1) ,'odds',SUBSTRING_INDEX(person, ':', -1) ))
FROM table_name,
JSON_TABLE(json, '$[*]' COLUMNS (person VARCHAR(40) PATH '$') people;
Here is a Db fiddle you can refer
https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=801de9f067e89a48d45ef9a5bd2d094a