I have a table
I'd like to get the JSON result like this:
[
{
"Type":"I", //If group name is empty display ‘I’ otherwise, display ‘G’
"StartDate":"20/12/2020 8:00am", //This is the start time
"Additional":{ //Because it is non-group (GroupName is null), so Additional is an object
"Info":"having food"
}
},
{
"Type":"G", //Group by Date and Group Name.
"GroupName":"School", //If record has the same group name,
"StartDate":"20/12/2020 9:00am", //!!! Display the first entry’s start date
"Additional":[ // It is an array due to Group Name being a real value, the items in array is the record whose StartDate has the same Date value.
{
"StartDate":"20/12/2020 9:00am", //Display the start date
"Info":"Take bus"
},
{
"StartDate":"20/12/2020 9:30am",", //Display the start date
"Info":"On the beach"
}
]
},
{
"Type":"G",
"GroupName":"Class 1",
"StartDate":"20/12/2020 11:00am",
"Additional":[
{
"StartDate":"20/12/2020 11:00am",
"Info":"Restaurant "
},
{
"StartDate":"20/12/2020 13:00pm",
"Info":"Walk on Lane"
}
]
},
{
"Type":"I",
"StartDate":"20/12/2020 15:00pm",
"Additional":{
"Info":"In museum"
}
}
]
Would any one help me on this? Thank you so much.
I also attach the JSON data in this picture so the JSON format would be clearer.
There is a typo sorry, this is the new picture:
As per Microsoft SQL Server documentation, FOR JSON, will work best for you. It is supported on SQL Server 2016 and above.
SELECT CASE
WHEN GroupName is null THEN 'I'
ELSE 'G'
END as Type
,GroupName
,StartDate .....
FROM table
FOR JSON AUTO;
https://learn.microsoft.com/en-us/sql/relational-databases/json/format-query-results-as-json-with-for-json-sql-server?view=sql-server-ver15
When you form a JSON structure. Better to use with "INCLUDE_NULL_VALUES". So that it will have NULL for attribute If the value is missing.
SELECT Column1, Column2,... FROM Table FOR JSON AUTO, INCLUDE_NULL_VALUES
Related
I'm trying to parse data from certain server, and need to export it to excel or csv.
before I export, I need to do some post processing such as merging values between parsed data.
for example,
There are two series out of all data.
series#1 - {Name: "MATH", Student:"Zay",Id:"MATH-123", Date:"12/25/2022", Status:"Good"}
series#2 - {Name: "MATH", Student:"Zay",Id:"MATH-124", Date:"12/26/2022", Status:"Bad"}
What I want to do is,
I want to update series#1's Status to
{Name: "MATH", Student:"Zay", Id:"MATH-123,MATH-124", Date:"12/25/2022,12/26/2022", Status:"Bad"}
Id, Date ==> combining with ","
Status ==> changing to latest result
Now I'm using Filter method of DataFrames,
type MyDataSet struct{
Name string
Student string
Id string
Date string
Status string
}
totalDF:=series1_result //overall result dataframe
df := dataframe.LoadStructs(series2_result) //new dataframe which needs to be compared to previous data `totalDF`
length := df.Nrow()
for i:=0;i<length;i++ {
name:=df.Subset(i).Col("Name")
student:=df.Subset(i).Col("Student")
query:= totalDF.Filter(
dataframe.F {
Colname:"Name",
Comparator:series.Eq,
Comparando:name,
},
).Filter(
dataframe.F {
Colname:"Student",
Comparator:series.Eq,
Comparando:student,
}
)
if query.Nrow()==0 {
totalDF = totalDF.Concat(df.Subset(i))
} else {
newDF:= dataframe.LoadStructs([]MyDataSet{
{
Name:query.Col("Name").String(),
Student:query.Col("Student").String(),
Id:query.Col("Id").String()+","+df.Subset(i).Col("Id").String(),
Date:query.Col("Date").String()+","+df.Subset(i).Col("Date").String(),
Status:df.Subset(i).Col("Status").String(),
}
})
query.Set(
series.Ints([]int{0}, newDF) //It's not updated as query was not an pointer
)
}
}
Even though I updated values on result of query, it's not updated on totalDF
How can I query the data from totalDF and update the data on that totalDF?
How can I get index number of Filtered item using Filter function?
Should I implement search function instead of using Filter function?
I would really appreciate it if you could help me.
Thanks everyone!
Merry Christmas!
*I tried to find out from official docs.
*But every method returns Value, not Pointer.
I have a table called groups where I have a field "group_users".
In every group the group_users is stored as json like this:
{
"user1": {
"name":"...",
"notifications": true,
}
"user2": {
...
}
}
How do I fetch every group that a certain user is apart of?
Thanks in advance :)
With Postgres 13, you can use a JSON path expression:
select *
from groups
where group_users ## 'strict $.**.name == "Someuser"'
This assumes that group_users is a jsonb column which it should be. If it's not you need to cast it group_users::jsonb
I have a table with a column of the data type JSONB. Each row in the column has a JSON that looks something like this:
[
{
"A":{
"AA": "something",
"AB": false
}
},
{
"B": {
"BA":[
{
"BAAA": [1,2,3,4]
},
{
"BABA": {
....
}
}
]
}
}
]
Note: the JSON is a complete mess of lists and objects, and it has a total of 300 lines. Not my data but I am stuck with it. :(
I am using postgresql version 12
How would I write the following queries:
Return all row that has the value of AB set to false.
Return the values of BAAA is each row.
You can find the AB = false rows with a JSON Path query:
select *
from test
where data ## '$[*].A.AB == false'
If you don't know where exactly the key AB is located, you can use:
select *
from test
where data ## '$[*].**.AB == false'
To display all elements from the array as rows, you can use:
select id, e.*
from test
cross join jsonb_array_elements(jsonb_path_query_first(data, '$[*].B.BA.BAAA')) with ordinality as e(item, idx)
I include a column "id" as a placeholder for the primary key column, so that the source of the array element can be determined in the output.
Online example
I'm trying to parse a the below nested JSON in Snowflake using the latteral function in Snowflake but I wanted to each nested column in "GoalTime" to show up as a column. For example,
GoalTime_InDoorOpen
2020-03-26T12:58:00-04:00
GoalTime_InLastOff
null
GoalTime_OutStartBoarding
2020-03-27T14:00:00-04:00
"GoalTime": [
{
"GoalName": "GoalTime_InDoorOpen",
"GoalTime": "2020-03-26T12:58:00-04:00"
},
{
"GoalName": "GoalTime_InLastOff"
},
{
"GoalName": "GoalTime_InReadyToTow"
},
{
"GoalName": "GoalTime_OutTowAtGate"
},
{
"GoalName": "GoalTime_OutStartBoarding",
"GoalTime": "2020-03-27T14:00:00-04:00"
},
or if you have many rows (what appear to be flights) and thus you need to columns per flight this code be what you are after
with data as (
select flight_code, parse_json(json) as json from values ('nz101','{GoalTime:[{"GoalName": "GoalA", "GoalTime": "2020-03-26T12:58:00-04:00"}, {"GoalName": "GoalB"}]}'),
('nz201','{GoalTime:[{"GoalName": "GoalA"}, {"GoalName": "GoalB", "GoalTime": "2020-03-26T12:58:00-02:00"}]}')
j(flight_code, json)
), unrolled as (
select d.flight_code, f.value:GoalName as goal_name, f.value:GoalTime as goal_time
from data d,
lateral flatten (input => json:GoalTime) f
)
select *
from unrolled
pivot(min(goal_time) for goal_name in ('GoalA', 'GoalB'))
order by flight_code;
it gives the results:
FLIGHT_CODE 'GoalA' 'GoalB'
nz101 "2020-03-26T12:58:00-04:00" null
nz201 null "2020-03-26T12:58:00-02:00"
create or replace function JSON_STRING()
returns string
language javascript
as
$$
return `
[
{
"GoalName": "GoalTime_InDoorOpen",
"GoalTime": "2020-03-26T12:58:00-04:00"
},
{
"GoalName": "GoalTime_InLastOff"
},
{
"GoalName": "GoalTime_InReadyToTow"
},
{
"GoalName": "GoalTime_OutTowAtGate"
},
{
"GoalName": "GoalTime_OutStartBoarding",
"GoalTime": "2020-03-27T14:00:00-04:00"
}
]
`;
$$;
select value:GoalName::string as GoalName, value:GoalTime::timestamp as GoalTime
from lateral flatten(input => parse_json(JSON_STRING()));
-- See how the lateral flatten combination works on a JSON variant:
select * from lateral flatten(input => parse_json(JSON_STRING()));
I wrote this to run in any Snowflake worksheet, no tables needed. The function on top simply allows the JSON to be written as a multi-line string in the SQL statement below it. It has no other use than representing a string holding your JSON.
Step 1 is to PARSE_JSON, which converts a string into a variant data type formatted as a JSON object.
Step 2 is the lateral flatten. If you do a select star on that, it will return a number of columns. One of them is "value".
Step 3 is to extract the properties you want using single : notation for the property name and dots to traverse down the nodes from there (if there are any).
Step 4 is to cast the property to the data type you want using double :: notation. This is especially important if you're doing comparisons on the column particularly in join keys.
Note that there's a slight invalid part of the JSON that did not allow it to parse. In the top level the array had a property, which did not parse. I removed that to allow parsing.
Probably close to what you seek is using a standard SQL UNION statement.
Given the following are true to recreate the solution:
Created a table 'JSON_GOALS' with one column for raw JSON called, GOALS_RAW
You have loaded JSON data into a table as the raw JSON, with compliant JSON object array syntax, and a parent, GoalTimeGroup, ex: {[{}]}, so
{
"GoalTimeGroup": [{
"GoalName": "GoalTime_InDoorOpen",
"GoalTime": "2020-03-26T12:58:00-04:00"
},
{
"GoalName": "GoalTime_InLastOff"
},
{
"GoalName": "GoalTime_InReadyToTow"
},
{
"GoalName": "GoalTime_OutTowAtGate"
},
{
"GoalName": "GoalTime_OutStartBoarding",
"GoalTime": "2020-03-27T14:00:00-04:00"
}
]
}
Doing so allows you to write a fairly standard JSON retrieve in Snowflake with the following syntax:
SELECT GOALS_RAW:GoalTimeGroup[0].GoalName, GOALS_RAW:GoalTimeGroup[1].GoalName, GOALS_RAW:GoalTimeGroup[2].GoalName
FROM JSON_GOALS
UNION
SELECT GOALS_RAW:GoalTimeGroup[0].GoalTime, GOALS_RAW:GoalTimeGroup[1].GoalTime, GOALS_RAW:GoalTimeGroup[2].GoalName
FROM JSON_GOALS
;
This gives you closer to the answer you are looking for and seems to provide a simpler solution. You can also control how many rows you'd want based on your JSON object attributes for each GOAL object.
Recommendations to enhance this would be to create a function that could detect the depth of each nested element and perhaps auto generate the indexes for 'n' number of columns.
The library below provides a method called "ExecuteAll" which one of the params is "tags", so if you provide an array of tags and values, all of them will be parsed and validated plus keeping the features of the sql injection protection from Snowflake.
snowflake-multisql
I have the following JSON array stored on a row:
{
"openings": [
{
"visibleFormData": {
"productName": "test"
}
}
]
}
I'm trying to get the value of productName. So far I've tried something like this:
SELECT tbl.column->'openings'->'0'->'visibleFormData'->>'productName'
The theory being that this would grab the first object (index 0) in the openings array and then grab the productName attribute from that object's visibleFormData object.
All I'm getting is null, though. I've tried multiple configurations of this. I'm thinking it has to do with the grabbing of index zero, but I am unsure. I am not a regular PSQL user, so it's proving a tad tricky to debug.
The json array index is integer, so use 0 instead of '0':
with tbl(col) as (
values
('{
"openings": [
{
"visibleFormData": {
"productName": "test"
}
}
]
}'::jsonb)
)
SELECT tbl.col->'openings'->0->'visibleFormData'->>'productName'
FROM tbl
?column?
----------
test
(1 row)