I'm trying to update a specific value in JSON array from a MySQL column by searching for specific ID, I want it to be dynamic without specifying array key.
Here is what I tried:
update myTable JSON_REPLACE(`data`, $.OD, '3/1')
where JSON_EXTRACT(`data`, '$.ID') = 'some id';
Here is my column data:
[
{"ID":63010092,"IT":"OV80419947-63010092_1_3","OD":"21/10","SU":0,"OR":0},
{"ID":63010093,"IT":"OV80419947-63010093_1_3","OD":"8/5","SU":0,"OR":1},
{"ID":63010094,"IT":"OV80419947-63010094_1_3","OD":"8/5","SU":0,"OR":2}
]
Try (adjust everything you consider necessary):
UPDATE `myTable`
INNER JOIN JSON_TABLE(
`myTable`.`data`,
'$[*]'
COLUMNS(
`position` FOR ORDINALITY,
`ID` INT PATH '$.ID'
)
) `der`
SET `data` = JSON_REPLACE(
`myTable`.`data`,
CONCAT('$[', `der`.`position` - 1, '].OD'),
'3/1'
)
WHERE `der`.`ID` = 63010092;
See dbfiddle.
Related
I have a database column (named "details") formatted as a JSON object that contains the following data:
'{"300-000012": {"is_complete": "False", "is_in_progress": "True"},
"300-000018": {"is_complete": "True", "is_in_progress": "False"}}'
I can't seem to convert the Array into Columns. I've tried
SELECT mh.*, jt.*
FROM history AS mh,
JSON_TABLE (mh.details, '$[*]'
COLUMNS (
NESTED PATH '$.*' COLUMNS (jt_complete VARCHAR(255) PATH '$.is_complete'),
NESTED PATH '$.*' COLUMNS (jt_progress VARCHAR(255) PATH '$.is_in_progress')
)
) AS jt)
But I get an Error Code
Error Code: 3143. Invalid JSON path expression
Ideally I would get something like:
details jt_complete jt_progress
300-000012 FALSE TRUE
300-000018 TRUE FALSE
Any help would be appreciated. Thx
This is a tricky one because the keys of the object are variable. This means you need to extract the keys and the values separately for each object. The values can be connected by using an ordinality column for each JSON_TABLE and joining them on that:
SELECT mh.id, jk.details, jt.jt_complete, jt.jt_progress
FROM history mh
JOIN JSON_TABLE(
JSON_KEYS(mh.details),
'$[*]' COLUMNS (
rn FOR ORDINALITY,
details VARCHAR(10) PATH '$'
)
) jk
JOIN JSON_TABLE(
JSON_EXTRACT(mh.details, '$.*'),
'$[*]' COLUMNS (
rn FOR ORDINALITY,
jt_complete VARCHAR(10) PATH '$.is_complete',
jt_progress VARCHAR(10) PATH '$.is_in_progress'
)
) jt ON jt.rn = jk.rn
Demo on dbfiddle
Hello I want to extract the different field values of a json object as key value pairs, but I'm not able to do that.
I tried this
SELECT JSON_EXTRACT(chapters, '$[*].Id', '$[*].Name') AS rec
FROM `Novels`
WHERE 1
but it result looks like this
["1","first Name","2","second name"]
any idea on how to convert it to something like this
{"1":"first Name","2":"second name"}
Thanks in advance!
Depending on the result, the concerned value of the chapters column should be
'[ {"Id":"1","Name":"first name"}, {"Id":"2","Name":"second name"} ]'
JSON_EXTRACT() can be applied for each element of the array in order to determine Id values as keys part, and Name values as values part.
And then, JSON_UNQUOTE() can be applied to get rid of double-quotes while generating rows for each individual array elements. JSON_OBJECTAGG is used to aggregate all those extracted objects at the last step provided that MariaDB version is 10.5+:
WITH n AS
(
SELECT #i := #i + 1 AS rn,
JSON_UNQUOTE(JSON_EXTRACT(chapters, CONCAT('$[',#i-1,'].Id'))) AS js_id,
JSON_UNQUOTE(JSON_EXTRACT(chapters, CONCAT('$[',#i-1,'].Name'))) AS js_name
FROM information_schema.tables
CROSS JOIN ( SELECT #i := 0, chapters FROM `Novels` ) n
WHERE #i < JSON_LENGTH(JSON_EXTRACT(chapters, '$[*]'))
)
SELECT JSON_OBJECTAGG(js_id,js_name) AS Result
FROM n
A Workaround might be given for DB version prior to 10.5 as
SELECT CONCAT('{',
GROUP_CONCAT(
REPLACE(
REPLACE( JSON_OBJECT(js_id,js_name) , '}', '')
, '{', '')
)
, '}') AS Result
FROM n
Demo
One option uses json_table() to unnest the array to rows (available in MySQL 8 only) then aggregation:
select
t.*,
(
select json_objectagg('id', x.id, 'name', x.name)
from json_table(
t.chapter,
'$[*]'
columns (
id int path '$.Id',
name varchar(50) path '$.Name'
)
) as x
) as obj
from mytable t
I am trying to Insert/update a string (JSON). While inserting/Updating the value I get data truncation error.
I have tried making a JSON type column and passing an JSON_OBJECT() type but that fails as well.
select '''[{"id":"1202","title":"Asian","notes":"","active":"1"}]''';
CREATE TABLE mktesttable (
id int NOT NULL,
s VARCHAR(34530) NOT NULL
);
INSERT INTO mktesttable
select 1, '''[{"id":"1202","title":"Asian","notes":"","active":"1"}]''';
select * from mktesttable;
// That Works
INSERT INTO mktesttable
SELECT
patient_data.id,
CONCAT(
'''[{"id":"', patient_data.race,
'","title":"', list_options.title,
'","notes":"', list_options.notes,
'","active":"', list_options.active,
'"}]'''
) as s
FROM
patient_data
INNER JOIN list_options
ON patient_data.race = list_options.id order by 1 desc
Yields same result (Id's and data varies) but doesn't work
Result Set
If you want to store JSON object, you should use the JSON datatype instead of strings. To create a JSON object, you can use JSON_OBJECT.
CREATE TABLE mktesttable (
id int NOT NULL,
s JSON NOT NULL
);
INSERT INTO mktesttable
SELECT
patient_data.id,
JSON_OBJECT(
'id', patient_data.race,
'title', list_options.title,
'notes', list_options.notes,
'active', list_options.active,
)
FROM
patient_data
INNER JOIN list_options
ON patient_data.race = list_options.id
ORDER BY patient_data.id desc
If you need a JSON array as shown in your sample data, then :
JSON_ARRAY(
JSON_OBJECT(
'id', patient_data.race,
'title', list_options.title,
'notes', list_options.notes,
'active', list_options.active,
)
)
How can I update an object in an array based on a unique value in the object?
Let's say this is my json object stored in a table called objects and in a column called content
table: objects
id: 7383
content: { data:[{id: 111, active: 1 }, {id: 222, active: 1 }, {id: 333, active: 0 }] }
I can update objects if I know the position of the element in the array with
SET content = JSON_REPLACE(content,'$.data[1].active', 0)
Where id = 7383
However, if I don't know the position of the array, but I do know the value of id (for example 222) in the object, how can I update active to 0 for the object that has id: 222 ?
Currently, it's complicated to look up numerical values with MySQL JSON functions. In a JSON like the following, it would be simple:
{"id": "222", "active": 1}
There are many ways to get what you need, I present one that can give you ideas (modify everything that is necessary):
UPDATE `objects`
SET `objects`.`content` =
JSON_REPLACE(`objects`.`content`, CONCAT('$.data',
(SELECT
JSON_UNQUOTE(
REPLACE(
JSON_SEARCH(
REPLACE(
REPLACE(
REPLACE(
`der`.`content` ->> '$.data[*].id',
', ',
'","'),
']',
'"]'),
'[',
'["'),
'one',
'222'),
'$',
'')
)
FROM (SELECT `objects`.`content`
FROM `objects`
WHERE `objects`.`id` = 7383) `der`
), '.active'), 0)
WHERE `objects`.`id` = 7383;
Beware of possible performance problems.
See dbfiddle.
In the most recent version of MySQL (>= 8.0.4), the sentence would be much simpler:
UPDATE `objects`
INNER JOIN JSON_TABLE(
`objects`.`content`,
'$.data[*]' COLUMNS(
`rowid` FOR ORDINALITY,
`id` INT PATH '$.id'
)
) `der` ON `der`.`id` = 222
SET `objects`.`content` =
JSON_REPLACE(
`objects`.`content`,
CONCAT('$.data[', `der`.`rowid` - 1, '].active'),
0)
WHERE
`objects`.`id` = 7383;
See db-fiddle.
It can be achieved by combining the functions JSON_SEARCH, which returns a dirty json path to the item you need, and then, extract the value of the jsonpath with an array index, concatenate it with subpath we want to update and use JSON_SET to set a new value to the final json path (tested with MySQL 5.7.32):
-- INPUT ------------------------------------------------
-- unique value for an object in the array
SET #unique_value = "12345";
-- object field we want to update
SET #field_to_update = '.myField';
-- new value
SET #new_value = 1;
-- PROCESSING ------------------------------------------
-- Get json path to the item with specified #unique_value
-- RESULT: $.data[6].id
SET #temp_path = ( TRIM(BOTH '"' FROM ( SELECT JSON_SEARCH(json, 'one', #unique_value, NULL, "$.data")
FROM `my-table`
WHERE `column1` = "abcd" ) ));
-- We are looking for the bracket that delimits index within the array of documents: [11]
SET #closing_bracket_index = (SELECT LOCATE(']', #temp_path));
-- Get json path with index of an object for #unique_value
-- in MySQL, string indexing starts from position 1, not a zero
-- RESULT: $.data[6]
SET #item_path = ( SELECT SUBSTRING(#temp_path, 1, #closing_bracket_index) );
-- $.data[6].myFIeld
SET #item_path_to_update = ( SELECT CONCAT(#item_path, #field_to_update) );
-- UPDATE JSON STATEMENT
UPDATE `my-table`
SET json = JSON_SET(json-column, #item_path_to_update, #new_value)
WHERE `column1` = "abcd";
Using only the native JSON fuctions (no PHP, etc) in MySQL version 5.7.12 (section 13.16 in the manual) I am trying to write a query to generate a JSON document from relational tables that contains a sub object. Given the following example:
CREATE TABLE `parent_table` (
`id` int(11) NOT NULL,
`desc` varchar(20) NOT NULL,
PRIMARY KEY (`id`)
);
CREATE TABLE `child_table` (
`id` int(11) NOT NULL,
`parent_id` int(11) NOT NULL,
`desc` varchar(20) NOT NULL,
PRIMARY KEY (`id`,`parent_id`)
);
insert `parent_table` values (1,'parent row 1');
insert `child_table` values (1,1,'child row 1');
insert `child_table` values (2,1,'child row 2');
I am trying to generate a JSON document that looks like this:
[{
"id" : 1,
"desc" : "parent row 1",
"child_objects" : [{
"id" : 1,
"parent_id" : 1,
"desc" : "child row 1"
}, {
"id" : 2,
"parent_id" : 1,
"desc" : "child row 2"
}
]
}]
I am new to MySQL and suspect there is a SQL pattern for generating nested JSON objects from one to many relationships but I'm having trouble finding it.
In Microsoft SQL (which I'm more familiar with) the following works:
select
[p].[id]
,[p].[desc]
,(select * from [dbo].[child_table] where [parent_id] = [p].[id] for json auto) AS [child_objects]
from [dbo].[parent_table] [p]
for json path
I attempted to write the equivalent in MySQL as follows:
select json_object(
'id',p.id
,'desc',p.`desc`
,'child_objects',(select json_object('id',id,'parent_id',parent_id,'desc',`desc`)
from child_table where parent_id = p.id)
)
from parent_table p;
select json_object(
'id',p.id
,'desc',p.`desc`
,'child_objects',json_array((select json_object('id',id,'parent_id',parent_id,'desc',`desc`)
from child_table where parent_id = p.id))
)
from parent_table p
Both attempts fail with the following error:
Error Code: 1242. Subquery returns more than 1 row
The reason you are getting these errors is that the parent json object is not expecting a result set as one of its inputs, you need to have simple object pairs like {name, string} etc bug report - may be available in future functionality... this just means that you need to convert your multi row results into a concatination of results separated by commas and then converted into a json array.
You almost had it with your second example.
You can achieve what you are after with the GROUP_CONCAT function
select json_object(
'id',p.id
,'desc',p.`desc`
,'child_objects',json_array(
(select GROUP_CONCAT(
json_object('id',id,'parent_id',parent_id,'desc',`desc`)
)
from child_table
where parent_id = p.id))
)
from parent_table p;
This almost works, it ends up treating the subquery as a string which leaves the escape characters in there.
'{\"id\": 1,
\"desc\": \"parent row 1\",
\"child_objects\":
[\"
{\\\"id\\\": 1,
\\\"desc\\\": \\\"child row 1\\\",
\\\"parent_id\\\": 1
},
{\\\"id\\\": 2,
\\\"desc\\\": \\\"child row 2\\\",
\\\"parent_id\\\": 1}\"
]
}'
In order to get this working in an appropriate format, you need to change the way you create the JSON output as follows:
select json_object(
'id',p.id
,'desc',p.`desc`
,'child_objects',(select CAST(CONCAT('[',
GROUP_CONCAT(
JSON_OBJECT(
'id',id,'parent_id',parent_id,'desc',`desc`)),
']')
AS JSON) from child_table where parent_id = p.id)
) from parent_table p;
This will give you the exact result you require:
'{\"id\": 1,
\"desc\": \"parent row 1\",
\"child_objects\":
[{\"id\": 1,
\"desc\": \"child row 1\",
\"parent_id\": 1
},
{\"id\": 2,
\"desc\": \"child row 2\",
\"parent_id\": 1
}]
}'
For MariaDb, CAST AS JSON does not work. But JSON_EXTRACT may be used to convert a string to a JSON object:
select json_object(
'id',p.id
,'desc',p.`desc`
,'child_objects',JSON_EXTRACT(IFNULL((select
CONCAT('[',GROUP_CONCAT(
json_object('id',id,'parent_id',parent_id,'desc',`desc`)
),']')
from child_table where parent_id = p.id),'[]'),'$')
) from parent_table p;
I tried group_concat solution but I found it's problems larger string because of group_concat limitations (group_concat_max_len).
I wrote the new function resolve the problem about converting a string to JSON object as bellow and how to use it.
Tested on MariaDB 10.5.12
Usage: https://i.stack.imgur.com/cWfd7.jpg
CREATE FUNCTION `ut_tf_array`(input_json longtext) RETURNS longtext CHARSET utf8mb4 COLLATE utf8mb4_unicode_ci
COMMENT 'Function for transform json array agg'
BEGIN
DECLARE transformed_data_list longtext ;
DECLARE record longtext ;
DECLARE i_count int ;
DECLARE i_count_items int ;
SET i_count = 0;
SET i_count_items = JSON_LENGTH(JSON_EXTRACT(input_json,'$'));
SET transformed_data_list = '[]';
-- return array with length = zero
IF input_json is NULL THEN
RETURN transformed_data_list;
END IF;
WHILE i_count < i_count_items DO
-- fetch into record
SELECT JSON_EXTRACT( JSON_EXTRACT( input_json ,'$') , CONCAT('$[',i_count,']')) INTO record;
-- append to transformed_data_list
SELECT JSON_ARRAY_APPEND(transformed_data_list, '$', JSON_EXTRACT(record, '$')) into transformed_data_list;
SET i_count := i_count + 1;
END WHILE;
-- done
RETURN transformed_data_list;
END
Below Query works for me.
SELECT JSON_ARRAYAGG(JSON_OBJECT('Id', p.id, 'desc', p.`desc`, 'child_objects', temp_json)) AS json_value
FROM (
SELECT p.id, p.`desc`,
JSON_ARRAYAGG(JSON_OBJECT('id', p.id, 'parent_id', p.parent_id, 'desc', p.`desc`)) AS temp_json
FROM parent_table p
GROUP BY p.id
) t;