SELECT with temporary column with value based on other column - mysql

I have mysql table which schema resembles the json array below.
[
{ "id": 1, "firstName": "Charles Montgomery", "lastName": "Burns", "managerId": 12},
{ "id": 2, "firstName": "Bart", "lastName": "Simpson", "managerId": 1},
{ "id": 3, "firstName": "Marge", "lastName": "Simpson", "managerId": 1},
{ "id": 4, "firstName": "Lisa", "lastName": "Simpson", "managerId": 1},
{ "id": 5, "firstName": "Maggie", "lastName": "Simpson", "managerId": 1},
{ "id": 6, "firstName": "Homer", "lastName": "Simpson", "managerId": 4},
{ "id": 7, "firstName": "Ned", "lastName": "Flanders", "managerId": 4},
{ "id": 8, "firstName": "Krusty", "lastName": "The Clown", "managerId": 2},
{ "id": 9, "firstName": "Waylon", "lastName": "Smithers", "managerId": 2},
{ "id": 10, "firstName": "Ralph", "lastName": "Wiggum", "managerId": 5},
{ "id": 11, "firstName": "Itchy", "lastName": "", "managerId": 5},
{ "id": 12, "firstName": "Comic Book Guy", "lastName": "", "managerId": 4}
]
managerId field is self referencing foreign key to the id field.
I need to make a query which will add column on the fly with "managerName" computed from id field which will hold concatenated firstName and lastName.
Below is (simplified) query that I've tried. Question mark is placeholder filled by mysql driver (in nodejs):
SELECT * ,
(SELECT CONCAT_WS(' ', firstName, lastName) FROM employee WHERE managerId = id ) as managerName
FROM employee WHERE employee.id = ?;
I realize this WHERE managerId = id is the place to look, but I honestly don't know what condition to place to match correct values.
Can anyone help?
EDIT
In case someone stumbles upon same thing, I've found helpful article. Even examples are similar.

LEFT JOIN is your friend. tra to use a query like this:
SELECT
e.*,
CONCAT_WS(' ', m.firstName, m.lastName) AS managerName
FROM employee e WHERE e.employee.id = ?
LEFT JOIN employee m ON e.managerId = m.id;

Related

Oracle JSON api - update single record in json collection

I have CLOB field with JSON data :
[
{
"name": "Rahul",
"LName": "Sharma",
"salary": "20000",
"Age": "35"
},
{
"name": "Kunal",
"LName": "Vohra",
"salary": "10000",
"Age": "25"
}
]
and I need update value in only one element of that array, for example in record with name: Kunal I need change salary.
I try json_transform() but with this I transform every field salary to new value.
json_transform(json_field_in_table, SET '$.salary' = 15000)
You may use filter expression in JSON path of json_transform function to update specific objects:
with a(col) as (
select q'$[
{
"name": "Rahul",
"LName": "Sharma",
"salary": "20000",
"Age": "35"
},
{
"name": "Kunal",
"LName": "Vohra",
"salary": "10000",
"Age": "25"
}
]$' from dual
)
select
json_transform(
col,
set '$[*]?(#.name == "Kunal").salary' = '100'
) as res
from a
RES
[{"name":"Rahul","LName":"Sharma","salary":"20000","Age":"35"},{"name":"Kunal","LName":"Vohra","salary":"100","Age":"25"}]
fiddle
Note that "10000" is a string in JSON, numbers should be used without quotes: {"salary: 10000}
You can't use json_transform because json_transform, json_exists... evaluate on the whole JSON document not on pieces of it,
even a json_exists with "'$?(#.name == "Kunal")'" will consider that the whole document matches and then update all "salary" fields.
(https://docs.oracle.com/en/database/oracle/oracle-database/12.2/adjsn/condition-JSON_EXISTS.html#GUID-8A0043D5-95F8-4918-9126-F86FB0E203F0)
but you can:
select json_arrayagg(json_object (
'name' value name,
'LName' value lname,
'salary' value case when name = 'Kunal' then 15000 else salary end,
'Age' value age)) as js
from
json_table(q'~[
{
"name": "Rahul",
"LName": "Sharma",
"salary": "20000",
"Age": "35"
},
{
"name": "Kunal",
"LName": "Vohra",
"salary": "10000",
"Age": "25"
}
]~','$[*]'
columns (
name VARCHAR2(64) path '$.name',
LName VARCHAR2(64) path '$.LName',
salary NUMBER path '$.salary',
age NUMBER path '$.Age'
));

How to generate nested nth level JSON object in T-SQL?

I have below data
against below query
declare #t table
(
Id int identity,
name varchar(50),
rootid int,
level int
);
insert into #t(name, rootid, level)
values
('Home', 0, 0)
,('Transaction', 0, 0)
, ('Settings', 0, 0)
,('Purchase Request', 2, 1)
,('Purchase Order', 2, 1)
,('Inventory', 2, 1)
,('Payment Advice', 2, 1)
,('Setup', 3, 1)
,('Budget', 3, 1)
,('CRC', 3, 1)
,('Create PR', 4, 3);
select * from #t;
Desire output:
[{
"Id": 1,
"name": "Home",
"rootid": 0,
"level": 0
}, {
"Id": 2,
"name": "Transaction",
"rootid": 0,
"level": 0,
"children": [{
"Id": 4,
"name": "Purchase Request",
"rootid": 2,
"level": 1,
"children": [{
"Id": 11,
"name": "Create PR",
"rootid": 4,
"level": 3
}]
}, {
"Id": 5,
"name": "Purchase Order",
"rootid": 2,
"level": 1
}, {
"Id": 6,
"name": "Inventory",
"rootid": 2,
"level": 1
}, {
"Id": 7,
"name": "Payment Advice",
"rootid": 2,
"level": 1
}]
}, {
"Id": 3,
"name": "Settings",
"rootid": 0,
"level": 0,
"children": [{
"Id": 8,
"name": "Setup",
"rootid": 3,
"level": 1
}, {
"Id": 9,
"name": "Budget",
"rootid": 3,
"level": 1
}, {
"Id": 10,
"name": "CRC",
"rootid": 3,
"level": 1
}]
}]
Also Tried #Iptr answer:
;WITH result (id, name, rootId, parent, Level) AS
(
SELECT id,
name,
RootId,
Id as Parent,
0 as Level
FROM #t
WHERE RootId= 0
UNION ALL
SELECT t.id,
t.Name,
t.RootId,
r.Parent,
r.Level + 1
FROM #t t
INNER JOIN result r ON r.id = t.RootId
)
SELECT t.*, json_query(nullif(c.children, '[{}]')) as children
FROM #t as t
outer apply (
select
(
select r.*
from result as r
where r.parent = t.Id
and r.level > 0
order by r.id
for json auto
) as children
) as c
where t.level = 0
order by t.Level
for json auto;
Output
[{
"Id": 1,
"name": "Home",
"rootid": 0,
"level": 0
}, {
"Id": 2,
"name": "Transaction",
"rootid": 0,
"level": 0,
"children": [{
"id": 4,
"name": "Purchase Request",
"rootId": 2,
"parent": 2,
"Level": 1
}, {
"id": 5,
"name": "Purchase Order",
"rootId": 2,
"parent": 2,
"Level": 1
}, {
"id": 6,
"name": "Inventory",
"rootId": 2,
"parent": 2,
"Level": 1
}, {
"id": 7,
"name": "Payment Advice",
"rootId": 2,
"parent": 2,
"Level": 1
}, {
"id": 11,
"name": "Create PR",
"rootId": 4,
"parent": 2,
"Level": 2
}]
}, {
"Id": 3,
"name": "Settings",
"rootid": 0,
"level": 0,
"children": [{
"id": 8,
"name": "Setup",
"rootId": 3,
"parent": 3,
"Level": 1
}, {
"id": 9,
"name": "Budget",
"rootId": 3,
"parent": 3,
"Level": 1
}, {
"id": 10,
"name": "CRC",
"rootId": 3,
"parent": 3,
"Level": 1
}]
}]
Above query is not returning nth json child objects, let say if I have nth level of menu items, Parent have multiple Childs and Childs have multiple Childs like treeview.
Tried #Naveen Arora answer:
select ID,name,'' as id,'' as name from Navigations where id not in (select rootid from Navigations) and rootid=0
union
select B.id,B.name,A.id,A.name from Navigations A join Navigations B on A.rootid=B.id
FOR JSON AUTO;
But output
[{
"ID": 1,
"name": "Home",
"id": 0,
"name": ""
}, {
"ID": 2,
"name": "Transaction",
"id": 4,
"name": "Create PR"
}, {
"ID": 2,
"name": "Transaction",
"id": 5,
"name": "Generate PO"
}, {
"ID": 2,
"name": "Transaction",
"id": 6,
"name": "Create Receipt"
}, {
"ID": 2,
"name": "Transaction",
"id": 7,
"name": "Create Issue Request"
}, {
"ID": 2,
"name": "Transaction",
"id": 8,
"name": "Create Issue Note"
}, {
"ID": 2,
"name": "Transaction",
"id": 9,
"name": "Approve Payment Advice"
}, {
"ID": 3,
"name": "Settings",
"id": 11,
"name": "Navigation Management"
}, {
"ID": 11,
"name": "Navigation Management",
"id": 12,
"name": "Navigation & Form Mapping"
}]
Above output it's not include Childs node. Like in Settings I have Navigation Management -> Navigation & Form Mapping
If the sql server version is 2016 or newer than 2016 then you can use FOR JSON PATH.
Assuming that results are stored in test table. This is just to give you an idea how you can do this, may not give you the exact output but you can change it as per your requirement.
SELECT
t.Id AS 'Id',
t.Name AS 'Name',
children = (
SELECT A.id,A.name from test A join test B on A.rootid=B.id
FOR JSON PATH
)
FROM Test t
FOR JSON PATH;
And if it is older than 2016 then you may refer this.
declare #t table
(
Id int identity,
name varchar(50),
rootid int,
level int
);
insert into #t(name, rootid, level)
values
('Home', 0, 0),('Transaction', 0, 0), ('Settings', 0, 0),
('Create PR', 2, 1), ('Generate PO', 2, 1), ('Create Receipt', 2, 1), ('Create Issue Request', 2, 1), ('Create Issue Note', 2, 1), ('Approve Payment Advice', 2, 1),
('Navigation Management', 3, 1), ('Navigation & Form Mapping', 3, 1);
select * from #t;
;WITH result (id, name, rootId, parent, Level) AS
(
SELECT id,
name,
RootId,
Id as Parent,
0 as Level
FROM #t
WHERE RootId= 0
UNION ALL
SELECT t.id,
t.Name,
t.RootId,
r.Parent,
r.Level + 1
FROM #t t
INNER JOIN result r ON r.id = t.RootId
)
SELECT t.*, json_query(nullif(c.children, '[{}]')) as children
FROM #t as t
outer apply (
select
(
select r.*
from result as r
where r.parent = t.Id
and r.level > 0
order by r.id
for json auto
) as children
) as c
where t.level = 0
order by t.Level
for json auto;
SELECT t.*, json_query(nullif(c.children, '[{}]')) as children
FROM #t as t
outer apply (
select
(
select r.*
from #t as r
where r.rootid = t.Id
and r.level > 0
order by r.id
for json auto
) as children
) as c
where t.level = 0
order by t.Level
for json auto;
My apology for late posting my answer. But I really appreciate the efforts of #Iptr and #NaveenArora answer on my post. After I do some brain storming on my case I've finally found the way to do it.
Create this function:
create function [dbo].[fnUDFCreateJSON](#currentId int)
returns varchar(max)
begin
declare #json nvarchar(max)
IF #currentId <> 0
BEGIN
set #json =
(
select [ID], [Name], CSSClass, RouteURL, json_query(dbo.fnUDFCreateJSON([ID])) as SubNavigation
from dbo.Navigations
where RootId = #currentId
for json auto
);
END
ELSE
BEGIN
set #json =
(
select [ID], [Name], CSSClass, RouteURL, '' as SubNavigation from dbo.Navigations where RootId = 0
for json auto
);
END
return #json
end
and call it by using stored procedure:
CREATE PROCEDURE [dbo].[spGetStartupNavigations]
AS
BEGIN
SELECT
(SELECT
ID, Name, CSSClass, RouteURL,
JSON_QUERY (dbo.fnUDFCreateJSON(ID)) AS SubNavigation
FROM
dbo.Navigations
WHERE
RootId = 0
FOR JSON AUTO) AS Navigation
END
That's it.

how to implement sub select with where condition in sequelize

I have these tables:
products
stores
produuctProperties
with this structure
[
"products" :
{
"id": 1,
"orginalName": "146153-0100 ",
"title": null,
"stores": [
{
"id": 1,
"stock": 100,
"minOQ": 1,
"maxOQ": 0
},
{
"id": 2,
"stock": 100,
"minOQ": 1,
"maxOQ": 0,
}
],
"productproperties": [
{
"id": 1,
"productId": 1,
"propertyId": 8,
"propertyOptionId": 5
},
{
"id": 2,
"productId": 1,
"propertyId": 9,
"propertyOptionId": 11
},
{
"id": 3,
"productId": 1,
"propertyId": 10,
"propertyOptionId": 9
}
]
}
]
I want filter my products by selected options , Suppose the selected options are 11 and 9
how to implement below sql query in Sequelize 5.6 with findAll , where and... :
select * from products as p
inner join stores as sr on sr.productId = p.id
where (select count(*) from productProperties where propertyOptionId in (11,9) and productId = p.id) >= 2
I've found that using query builder in sequelize is really confusing,
so if you're good with raw sql you could just run them on as below
if Student is you're model
then
const students = Student.query('Select * from students');

How to make pgsql return the json array

everyone , I face some issue to convert the data into json object. There is a table called milestone with the following data:
id name parentId
a test1 A
b test2 B
c test3 C
I want to convert the result into a json type in Postgres:
[{"id": "a", "name": "test1", "parentId": "A"}]
[{"id": "b", "name": "test2", "parentId": "B"}]
[{"id": "c", "name": "test3", "parentId": "C"}]
if there are anyone know how to handle , please let me know , thanks all
You can get each row of the table as simple json object with to_jsonb():
select to_jsonb(m)
from milestone m
to_jsonb
-----------------------------------------------
{"id": "a", "name": "test1", "parentid": "A"}
{"id": "b", "name": "test2", "parentid": "B"}
{"id": "c", "name": "test3", "parentid": "C"}
(3 rows)
If you want to get a single element array for each row, use jsonb_build_array():
select jsonb_build_array(to_jsonb(m))
from milestone m
jsonb_build_array
-------------------------------------------------
[{"id": "a", "name": "test1", "parentid": "A"}]
[{"id": "b", "name": "test2", "parentid": "B"}]
[{"id": "c", "name": "test3", "parentid": "C"}]
(3 rows)
You can also get all rows as a json array with jsonb_agg():
select jsonb_agg(to_jsonb(m))
from milestone m
jsonb_agg
-----------------------------------------------------------------------------------------------------------------------------------------------
[{"id": "a", "name": "test1", "parentid": "A"}, {"id": "b", "name": "test2", "parentid": "B"}, {"id": "c", "name": "test3", "parentid": "C"}]
(1 row)
Read about JSON Functions and Operators in the documentation.
You can use ROW_TO_JSON
From Documentation :
Returns the row as a JSON object. Line feeds will be added between
level-1 elements if pretty_bool is true.
For the query :
select
row_to_json(tbl)
from
(select * from tbl) as tbl;
You can check here in DEMO

Flatten nested JSON structure in PostgreSQL

I'm trying to write a Postgres query that will output my json data in a particular format.
JSON data structure
{
user_id: 123,
data: {
skills: {
"skill_1": {
"title": "skill_1",
"rating": 4,
"description": 'description text'
},
"skill_2": {
"title": "skill_2",
"rating": 2,
"description": 'description text'
},
"skill_3": {
"title": "skill_3",
"rating": 5,
"description": 'description text'
},
...
}
}
}
This is how I need the data to be formatted in the end:
[
{
user_id: 123,
skill_1: 4,
skill_2: 2,
skill_3: 5,
...
},
{
user_id: 456,
skill_1: 1,
skill_2: 3,
skill_3: 4,
...
}
]
So far I'm working with a query that looks like this:
SELECT
user_id,
data#>>'{skills, "skill_1", rating}' AS "skill_1",
data#>>'{skills, "skill_2", rating}' AS "skill_2",
data#>>'{skills, "skill_3", rating}' AS "skill_3"
FROM some_table
There has to be a better way to go about writing my query. There are 400+ rows and 70+ skills. My above query is a little crazy. Any guidance or help would be greatly appreciated.
Some things to note:
Users rated themselves on 70+ skills
Each skill object has the same structure
Each user rated themselves on the exact same set of skills
db<>fiddle
I expanded your test data to (note the array around all users):
[{
"user_id": 123,
"data": {
"skills": {
"skill_1": {
"title": "skill_1",
"rating": 4,
"description": "description text"
},
"skill_2": {
"title": "skill_2",
"rating": 2,
"description": "description text"
},
"skill_3": {
"title": "skill_3",
"rating": 5,
"description": "description text"
}
}
}
},
{
"user_id": 456,
"data": {
"skills": {
"skill_1": {
"title": "skill_1",
"rating": 1,
"description": "description text"
},
"skill_2": {
"title": "skill_2",
"rating": 3,
"description": "description text"
},
"skill_3": {
"title": "skill_3",
"rating": 4,
"description": "description text"
}
}
}
}]
The query:
SELECT
jsonb_pretty(jsonb_agg(user_id || skills)) -- E
FROM (
SELECT
json_build_object('user_id', user_id)::jsonb as user_id, -- D
json_object_agg(skill_title, skills -> skill_title -> 'rating')::jsonb as skills
FROM (
SELECT
user_id,
json_object_keys(skills) as skill_title, -- C
skills
FROM (
SELECT
(datasets -> 'user_id')::text as user_id,
datasets -> 'data' -> 'skills' as skills -- B
FROM (
SELECT
json_array_elements(json) as datasets -- A
FROM (
SELECT '/* the JSON data; see db<>fiddle */'::json
)s
)s
)s
)s
GROUP BY user_id
ORDER BY user_id
)s
A Make all array elements ({user_id: '42', data: {...}}) one row each
B First column safe the user_id. The cast to text ist necessary for the GROUP BY later which cannot group JSON output. For the second column extract the skills data of the user
C Extract the skill titles for using them as keys in (D.1).
D.1 skills -> skill_title -> 'rating' extracts the rating value from each skill
D.2 json_object_agg aggregates the skill_titles and each corresponding rating value into one JSON object; grouped by the user_id
D.3 json_build_object makes the user_id a JSON object again
E.1 user_id || skills aggregates the two json object into one
E.2 jsonb_agg aggregates these json objects into an array
E.3 jsonb_pretty makes the result looking pretty.
Result:
[{
"skill_1": 4,
"skill_2": 2,
"skill_3": 5,
"user_id": "123"
},
{
"skill_1": 1,
"skill_2": 3,
"skill_3": 4,
"skill_4": 42,
"user_id": "456"
}]