MySQL 8 update with Replace() or Regex - mysql

Question

How can i update data using replace or regex-like method from
id | jdata
---------------
01 | {"name1":["number","2"]}
02 | {"val1":["number","12"],"val2":["number","22"]}
to
id | jdata
---------------
01 | {"name1":2 }
02 | {"val1": 12,"val2":22 }
I need to make a proper json entry for numbers and replace an array with a number from that array. Column "jdata" can have any number of similar attributes from the example. Something similar to this would do:
UPDATE table SET jdata = REPLACE(jdata, '["number","%d"]', %d);

Answer 1

Two ways:
The long, more clumsy way, using JSON_ARRAY:
UPDATE table1,
(
SELECT
id,
JSON_EXTRACT(jdata, "$.name1[0]") as A,
JSON_EXTRACT(jdata, "$.name1[1]") as B,
JSON_EXTRACT(jdata, "$.val1[0]") as C,
JSON_EXTRACT(jdata, "$.val1[1]") as D,
JSON_EXTRACT(jdata, "$.val2[0]") as E,
JSON_EXTRACT(jdata, "$.val2[1]") as F
FROM table1
) x
SET jdata = CASE WHEN table1.id=1 THEN JSON_ARRAY("name1",x.B)
ELSE JSON_ARRAY("val1",x.D,"val2",F) END
WHERE x.id=table1.id;
Or using JSON_REPLACE:
update table1
set jdata = JSON_REPLACE(jdata, "$.name1",JSON_EXTRACT(jdata,"$.name1[1]"))
where id=1;
update table1
set jdata = JSON_REPLACE(jdata, "$.val1",JSON_EXTRACT(jdata,"$.val1[1]"),
"$.val2",JSON_EXTRACT(jdata,"$.val2[1]"))
where id=2;
see: DBFIDDLE for both options
EDIT: To get more depth in the query, you can start with below, and create a new JSON message from this stuff without the number:
WITH RECURSIVE cte1 as (
select 0 as x
union all
select x+1 from cte1 where x<10
)
select
id,
x,
JSON_UNQUOTE(JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]"))) j,
JSON_EXTRACT(jdata,CONCAT("$.",JSON_UNQUOTE(JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]"))))) v,
JSON_UNQUOTE(JSON_EXTRACT(jdata,CONCAT("$.",JSON_UNQUOTE(JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]"))),"[0]"))) v1,
JSON_UNQUOTE(JSON_EXTRACT(jdata,CONCAT("$.",JSON_UNQUOTE(JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]"))),"[1]"))) v2
from table1
cross join cte1
where x<JSON_DEPTH(jdata)
and not JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]")) is null
order by id,x;
output:
id
x
j
v
v1
v2
1
0
name1
["number", "2"]
number
2
2
0
val1
["number", "12"]
number
12
2
1
val2
["number", "22"]
number
22
This should take care of JSON message which also contains values like val3, val4, etc, until a maximum depth which is now fixed to 10 in cte1.
EDIT2: When it is just needed to remove the "number" from the JSON message, you can also repeat this UPDATE until all "number" tags are removed (you can repeat this in a stored procedure, I am not going to write the stored procedure for you 😉)
update
table1,
( WITH RECURSIVE cte1 as (
select 0 as x
union all
select x+1 from cte1 where x<10
) select * from cte1 )x
set jdata = JSON_REMOVE(table1.jdata, CONCAT("$.",JSON_UNQUOTE(JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]"))),"[0]"))
where JSON_UNQUOTE(JSON_EXTRACT(jdata,CONCAT("$.",JSON_UNQUOTE(JSON_EXTRACT(JSON_KEYS(jdata),CONCAT("$[",x,"]"))),"[0]"))) = "number"
An example, where I do run the update 2 times, is in this DBFIDDLE