This is my query:
SELECT
JSON_QUERY(MyStringColumnWithJson, '$.Images') AS images
FROM MyTable
which returns a single field with the JSON data shown here below:
"{
"Images":
[
{"Name":"test1.jpeg","Description":"originalName1.jpeg"},
{"Name":"test2.jpeg","Description":"originalName2.jpeg"},
{"Name":"test3.jpeg","Description":"originalName3.jpeg"}
]
}"
How can I read the images result row by row into a temporary table structure?
Use OPENJSON which returns a data set, not JSON_VALUE, which returns a scalar value. For example:
DECLARE #JSON nvarchar(MAX) = N'{
"Images":
[
{"Name":"test1.jpeg","Description":"originalName1.jpeg"},
{"Name":"test2.jpeg","Description":"originalName2.jpeg"},
{"Name":"test3.jpeg","Description":"originalName3.jpeg"}
]
}';
SELECT *
FROM OPENJSON(#JSON, '$.Images')
WITH (Name nvarchar(128),
Description nvarchar(128))OJ;
SELECT I.[Name],
I.Description
FROM MyTable MT
CROSS APPLY OPENJSON(MT.YourJsonColumn, '$.Images')
WITH (Name nvarchar(128),
Description nvarchar(128)) I;
Related
I am using an API from Discovery to extract some information from our virtual machines but the JSON for some reasons have the headings in one node and the values in another and they are in square brackets and I am having a hard getting to the end result.
This is a watered-down version of the JSON
DECLARE #JSON nvarchar(max) = N'[
{
"headings": [
"vm_type",
"Hostname"
],
"results": [
[
"AWS EC2 Instance",
null
],
[
"AWS EC2 Instance",
null
]
]
}
]'
SET #JSON = SUBSTRING(#JSON,2,LEN(#JSON) - 2)
SELECT *
FROM OPENJSON(#JSON)
SELECT *
FROM OPENJSON(#JSON,'$.results')
Is there a way to turn this into a table with the headings as column names and the results in the same order as its value?
You have an array of arrays, so this is effectively a dynamic pivot.
To do a dynamic pivot you need dynamic SQL. The easiest way to pivot is not usually to use PIVOT but to use conditional aggregation with MAX(CASE
DECLARE #sql nvarchar(max) = N'
SELECT
' + (
SELECT STRING_AGG(
QUOTENAME(j.value) + N' = MAX(CASE WHEN j2.[key] = ' + j.[key] + ' THEN j2.value END)',
',
') WITHIN GROUP (ORDER BY j.[key])
FROM OPENJSON(#JSON, '$[0].headings') j
) + '
FROM OPENJSON(#JSON, ''$[0].results'') j1
CROSS APPLY OPENJSON(j1.value) j2
GROUP BY
j1.[key];
';
PRINT #sql; --for testing
EXEC sp_executesql
#sql,
N'#JSON nvarchar(max)',
#JSON = #JSON;
db<>fiddle
Note correct use of QUOTENAME to quote column names, and use of sp_executesql with a parameter to pass in actual data, rather than injecting it directly into the query text.
I have the following t-sql query that returns json:
SELECT
CF.Name
, UCF.Value
FROM dbo.ClaimsCustomFields CF
LEFT JOIN dbo.UserCustomFields UCF
ON UCF.FieldId = CF.Id
WHERE CF.CustomerId = 2653
FOR JSON PATH;
The output of this query is next:
[
{
"Name":"zipCode",
"Value":"zip zip zipC zipCod"
},
{
"Name":"time111zone",
"Value":"UTC +2"
},
{
"Name":"tttt",
"Value":"Company organization tessss"
}
]
But I want to get the result in the following format:
[
{
"zipCode":"zip zip zipC zipCod"
},
{
"time111zone":"UTC +2"
},
{
"tttt":"Company organization tessss"
}
]
Is it possible to achive this with FOR JSON statement?
You basically want to generate a dynamic json, so you can try to use dynamic TSQL taking advantage of SQL Server 2017 new function STRING_AGG (more info here):
--this table contains your sample data
declare #tmp table([Name] varchar(50),[Value] varchar(50))
--this variable will contain the dynamic tsql command
declare #sql nvarchar(max)
--this temp table will hold the dynamically generated json fragments
if object_id('#tmp') is null
create table #tmp (js varchar(max))
--fill table with test data
insert into #tmp values
('zipCode' ,'zip zip zipC zipCod'),
('time111zone' ,'UTC +2'),
('tttt' ,'Company organization tessss')
--generate a TSQL command that inserts each single JSON fragment into a temp table
select #sql = string_agg('insert into #tmp(js) values((select ''' + [Value] +''' as '''
+ [Name]+''' for json path , WITHOUT_ARRAY_WRAPPER))', ';')
from #tmp
--execute the dynamic TSQL command that fills the temp table with JSON fragments
exec(#sql)
--concatenate all the JSON fragments adding square brackets
select '[' + string_agg(js,',') + ']' as result from #tmp
Results:
[{"zipCode":"zip zip zipC zipCod"},{"time111zone":"UTC +2"},{"tttt":"Company organization tessss"}]
How can I read value from json file in that field name contains space using OPENJSON in Sql Server 2016. See the below code:
DECLARE #json NVARCHAR(MAX)
SET #json = N'{ "full name" : "Jayesh Tank"}';
SELECT * FROM OPENJSON(#json) WITH ( [name] [varchar](60) '$.full name')
Also another sample code in that space is after field name.
SET #json = N'{ "name " : "abc"}';
SELECT * FROM OPENJSON(#json) WITH ( [name] [varchar](60) '$.name')
'$.name' will return null.Is there way to read this value?
Generally it is a bad idea to use spaces in the attribute name.
I would leave out the [ ] from your OPENJSON name and varchar(60) - source MSDN OPENJSON.
Now to actually answer your question:
You need to format your attribute with double quotes in the WITH clause:
#DECLARE #json NVARCHAR(MAX);
SET #json=N'{ "full name" : "Jayesh Tank"}';
SELECT * FROM OPENJSON(#json) WITH (name varchar(60) '$."full name"')
for the second one:
SET #json = N'{ "name " : "abc"}';
SELECT * FROM OPENJSON(#json) WITH ( name varchar(60)'$."name "')
JSON_VALUE(c.value,'$.Serial Number') as [Serial Number] is throwing an error with a space. How do I resolve the space in the field name using JSON_VALUE .
by itself '$.Full Name' is not a valid json, but adding '$."Full Name"' the json becomes valid
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;
I have some json that I would like to parse in SQL Server 2016. There is a hierarchy structure of Projects->Structures->Properties. I would like to write a query that parses the whole hierarchy but I don't want to specify any elements by index number ie I don't want to do anything like this:
openjson (#json, '$[0]')
or
openjson (#json, '$.structures[0]')
I had this idea that I could read the values of the top level project objects along with the json string that represents the structures below it, which could then be parsed separately. The problem is that the following code does not work:
declare #json nvarchar(max)
set #json = '
[
{
"IdProject":"97A76363-095D-4FAB-940E-9ED2722DBC47",
"Name":"Test Project",
"structures":[
{
"IdStructure":"CB0466F9-662F-412B-956A-7D164B5D358F",
"IdProject":"97A76363-095D-4FAB-940E-9ED2722DBC47",
"Name":"Test Structure",
"BaseStructure":"Base Structure",
"DatabaseSchema":"dbo",
"properties":[
{
"IdProperty":"618DC40B-4D04-4BF8-B1E6-12E13DDE86F4",
"IdStructure":"CB0466F9-662F-412B-956A-7D164B5D358F",
"Name":"Test Property 2",
"DataType":1,
"Precision":0,
"Scale":0,
"IsNullable":false,
"ObjectName":"Test Object",
"DefaultType":1,
"DefaultValue":""
},
{
"IdProperty":"FFF433EC-0BB5-41CD-8A71-B5F09B97C5FC",
"IdStructure":"CB0466F9-662F-412B-956A-7D164B5D358F",
"Name":"Test Property 1",
"DataType":1,
"Precision":0,
"Scale":0,
"IsNullable":false,
"ObjectName":"Test Object",
"DefaultType":1,
"DefaultValue":""
}
]
}
]
}
]';
select IdProject, Name, structures
from openjson (#json)
with
(
IdProject uniqueidentifier,
Name nvarchar(100),
structures nvarchar(max)
) as Projects
IdProject and Name get returned no problem but for some reason I cannot get the nested json held in 'structures'. Instead of the json content it just returns NULL:
Does anyone know if this is possible and if so, what am I doing wrong?
Using CROSS APPLY:
declare #json nvarchar(max)
set #json = '
[
{
"IdProject":"97A76363-095D-4FAB-940E-9ED2722DBC47",
"Name":"Test Project",
"structures":[
{
"IdStructure":"CB0466F9-662F-412B-956A-7D164B5D358F",
"IdProject":"97A76363-095D-4FAB-940E-9ED2722DBC47",
"Name":"Test Structure",
"BaseStructure":"Base Structure",
"DatabaseSchema":"dbo",
"properties":[
{
"IdProperty":"618DC40B-4D04-4BF8-B1E6-12E13DDE86F4",
"IdStructure":"CB0466F9-662F-412B-956A-7D164B5D358F",
"Name":"Test Property 2",
"DataType":1,
"Precision":0,
"Scale":0,
"IsNullable":false,
"ObjectName":"Test Object",
"DefaultType":1,
"DefaultValue":""
},
{
"IdProperty":"FFF433EC-0BB5-41CD-8A71-B5F09B97C5FC",
"IdStructure":"CB0466F9-662F-412B-956A-7D164B5D358F",
"Name":"Test Property 1",
"DataType":1,
"Precision":0,
"Scale":0,
"IsNullable":false,
"ObjectName":"Test Object",
"DefaultType":1,
"DefaultValue":""
}
]
}
]
}
]';
select
Projects.IdProject, Projects.Name as NameProject,
Structures.IdStructure, Structures.Name as NameStructure, Structures.BaseStructure, Structures.DatabaseSchema,
Properties.*
from openjson (#json)
with
(
IdProject uniqueidentifier,
Name nvarchar(100),
structures nvarchar(max) as json
)
as Projects
cross apply openjson (Projects.structures)
with
(
IdStructure uniqueidentifier,
Name nvarchar(100),
BaseStructure nvarchar(100),
DatabaseSchema sysname,
properties nvarchar(max) as json
) as Structures
cross apply openjson (Structures.properties)
with
(
IdProperty uniqueidentifier,
NamePreoperty nvarchar(100) '$.Name',
DataType int,
[Precision] int,
[Scale] int,
IsNullable bit,
ObjectName nvarchar(100),
DefaultType int,
DefaultValue nvarchar(100)
)
as Properties
If you reference JSON object or array you need to specify AS JSON clause:
select IdProject, Name, structures
from openjson (#json)
with
(
IdProject uniqueidentifier,
Name nvarchar(100),
structures nvarchar(max) AS JSON
) as Projects
See FAQ: https://learn.microsoft.com/en-us/sql/relational-databases/json/solve-common-issues-with-json-in-sql-server?view=sql-server-ver15#return-a-nested-json-sub-object-from-json-text-with-openjson
If you want to apply OPENJSON on the returned structures array, you can use something like following code:
select IdProject, Name, structures
from openjson (#json)
with
(
IdProject uniqueidentifier,
Name nvarchar(100),
structures nvarchar(max) AS JSON
) as Projects
CROSS APPLY OPENJSON (structures) WITH (......)
Typical! I found the answer just after posting the question. You need to use the 'as json' key word when specifying the columns to return:
select IdProject, Name, structures
from openjson (#json)
with
(
IdProject uniqueidentifier,
Name nvarchar(100),
structures nvarchar(max) as json
) as Projects