How to create a column with rows in postgres? I want to create a table that withholds an array of values inside one column in table.

Example in JSON form:

 "trainNumber": 1,
 "departureDate": "2020-01-26",
 "operatorUICCode": 10,
 "operatorShortCode": "vr",
 "trainType": "IC",
 "trainCategory": "Long-distance",
 "commuterLineID": "",
 "runningCurrently": false,
 "cancelled": false,
 "version": 266667265768,
 "timetableType": "REGULAR",
 "timetableAcceptanceDate": "2019-11-08T10:34:22.000Z",
 "timeTableRows": [
   {
     "type": "DEPARTURE",
     "scheduledTime": "2020-01-26T04:57:00.000Z",
     "causes": []
   },
   {
     "type": "ARRIVAL",
     "scheduledTime": "2020-01-26T05:02:00.000Z",
     "causes": []
   },
   {
     "type": "DEPARTURE",
     "scheduledTime": "2020-01-26T05:03:00.000Z",
     "causes": []
   },
   {
     "type": "ARRIVAL",
     "causes": []
   },
   {
     "type": "DEPARTURE",
     "cancelled": false,
     "scheduledTime": "2020-01-26T05:05:00.000Z",
     "causes": []
   },


As show in example "timeTableRows".

How do I create this?
You could try adding a json array column (json[]), but it depends on your access patterns  what the best column type would be. 

Example:

ALTER TABLE tableName
ADD COLUMN timeTableRows json[];


And then:

INSERT INTO tableName 
(
    timeTableRows
) 
VALUES
( array['{
   "type": "DEPARTURE",
   "scheduledTime": "2020-01-26T04:57:00.000Z",
   "causes": []
 }',
 '{
   "type": "ARRIVAL",
   "scheduledTime": "2020-01-26T05:02:00.000Z",
   "causes": []
 }']::json[])