Parse JSON into Oracle table using PL/SQL

Question

I have created the following script in order to read data from Mobile App DB (which is based on MongoDB) from Oracle SQL Developer:

DECLARE
  l_param_list     VAR         


        

Answer 1

I used PL/JSON library. Specifically, JSON_EXT package functions in order to parse it.

The following script inspired by Oracle Community answer worked for me

DECLARE
  l_param_list     VARCHAR2(512);

  l_http_request   UTL_HTTP.req;
  l_http_response  UTL_HTTP.resp;

  l_response_text  VARCHAR2(32767);

l_list json_list;
A_id           VARCHAR2(200);
UserId         VARCHAR2(100);
UserName       VARCHAR2(100);
OutletCode     VARCHAR2(100);
OutletName     VARCHAR2(100);
MobileNumber   VARCHAR2(100);
PhoneNumber    VARCHAR2(100);
Address        VARCHAR2(100);
City           VARCHAR2(100);
State          VARCHAR2(100);
Postcode       VARCHAR2(100);
Email          VARCHAR2(100);
UpdateCount    VARCHAR2(100);
loginCount     VARCHAR2(100);
ReferencePhoto VARCHAR2(100);
Updates        VARCHAR2(100);
AccountLocked  VARCHAR2(100);
Oracle_Flag    VARCHAR2(100);
acl            VARCHAR2(100);


BEGIN

  -- service's input parameters

  -- preparing Request...
  l_http_request := UTL_HTTP.begin_request('https://api.appery.io/rest/1/db/collections/Outlet_Details?where=%7B%22Oracle_Flag%22%3A%22Y%22%7D'
                                          , 'GET'
                                          , 'HTTP/1.1');

  -- ...set header's attributes
  UTL_HTTP.set_header(l_http_request, 'X-Appery-Database-Id', '53f2dac5e4b02cca64021dbe');
  --UTL_HTTP.set_header(l_http_request, 'Content-Length', LENGTH(l_param_list));

  -- ...set input parameters
 -- UTL_HTTP.write_text(l_http_request, l_param_list);

  -- get Response and obtain received value
  l_http_response := UTL_HTTP.get_response(l_http_request);

  UTL_HTTP.read_text(l_http_response, l_response_text);

  DBMS_OUTPUT.put_line(l_response_text);
  l_list := json_list(l_response_text);

FOR i IN 1..l_list.count
LOOP
  A_id           := json_ext.get_string(json(l_list.get(i)),'_id');
  UserId         := json_ext.get_string(json(l_list.get(i)),'UserId');
  UserName       := json_ext.get_string(json(l_list.get(i)),'UserName');
  OutletCode     := json_ext.get_string(json(l_list.get(i)),'OutletCode');
  OutletName     := json_ext.get_string(json(l_list.get(i)),'OutletName');
  MobileNumber   := json_ext.get_string(json(l_list.get(i)),'MobileNumber');
  PhoneNumber    := json_ext.get_string(json(l_list.get(i)),'PhoneNumber');
  Address        := json_ext.get_string(json(l_list.get(i)),'Address');
  City           := json_ext.get_string(json(l_list.get(i)),'City');
  State          := json_ext.get_string(json(l_list.get(i)),'State');
  Postcode       := json_ext.get_string(json(l_list.get(i)),'Postcode');
  Email          := json_ext.get_string(json(l_list.get(i)),'Email');
  UpdateCount    := json_ext.get_string(json(l_list.get(i)),'UpdateCount');
  loginCount     := json_ext.get_string(json(l_list.get(i)),'loginCount');
  ReferencePhoto := json_ext.get_string(json(l_list.get(i)),'ReferencePhoto');
  Updates        := json_ext.get_string(json(l_list.get(i)),'Updates');
  AccountLocked  := json_ext.get_string(json(l_list.get(i)),'AccountLocked');
  Oracle_Flag    := json_ext.get_string(json(l_list.get(i)),'Oracle_Flag');
  acl            := json_ext.get_string(json(l_list.get(i)),'acl');


insert .....

Notice that json_ext.get_string retuns only VARCHAR2 limited to 32767 max. In order to use the same package with larger json_list and json_values (>32KB) check here.

If you have APEX 5.0 and above, better option and much better performance via APEX_JSON package. See @Olafur Tryggvason's answer for details

Answer 2

Orace provides PL/SQL DOM APIs for JSON handling. Strongly recommend using it, as it provides tons of useful APIs.

https://docs.oracle.com/database/122/ADJSN/using-PLSQL-object-types-for-JSON.htm#GUID-F0561593-D0B9-44EA-9C8C-ACB6AA9474EE

Answer 3

Since this question scores high in results, I want to post this preferred alternative:

Oracle has released APEX 5.0 (April 15. 2015). With it you get access to a great API to work with JSON

I'm using it on 11.2 and have been able to crunch every single json, from simple to very complex objects with multiple arrays and 4/5 levels. APEX_JSON

If you do not want to use APEX. Simply install the runtime environment to get access to the API.

Sample usage, data from json.org's example :

declare
    sample_json   varchar2 (32767)
        := '{
    "glossary": {
        "title": "example glossary",
        "GlossDiv": {
            "title": "S",
            "GlossList": {
                "GlossEntry": {
                    "ID": "SGML",
                    "SortAs": "SGML",
                    "GlossTerm": "Standard Generalized Markup Language",
                    "Acronym": "SGML",
                    "Abbrev": "ISO 8879:1986",
                    "GlossDef": {
                        "para": "A meta-markup language, used to create markup languages such as DocBook.",
                        "GlossSeeAlso": ["GML", "XML"]
                    },
                    "GlossSee": "markup"
                }
            }
        }
    }
}';
begin
    apex_json.parse (sample_json);
    dbms_output.put_line (apex_json.get_varchar2 ('glossary.GlossDiv.title'));
    dbms_output.put_line (apex_json.get_varchar2 ('glossary.GlossDiv.GlossList.GlossEntry.GlossTerm'));
    dbms_output.put_line (apex_json.get_varchar2 ('glossary.GlossDiv.GlossList.GlossEntry.GlossDef.GlossSeeAlso[%d]', 2));
end;

Result: PL/SQL block executed

S
Standard Generalized Markup Language
XML

Answer 4

in Oracle 12: https://docs.oracle.com/database/121/SQLRF/functions092.htm#SQLRF56973

SELECT jt.*
FROM j_purchaseorder,
JSON_TABLE(po_document, '$.ShippingInstructions.Phone[*]'
COLUMNS (row_number FOR ORDINALITY,
         phone_type VARCHAR2(10) PATH '$.type',
         phone_num VARCHAR2(20) PATH '$.number'))
AS jt;

ROW_NUMBER PHONE_TYPE PHONE_NUM
---------- ---------- --------------------
         1 Office     909-555-7307
         2 Mobile     415-555-1234