JSONB_EXTEND

Provides functions for PostgreSQL 9.4 to merge two or more jsonb values into one value.
Provided functions:

• jsonb_extend(a jsonb, b jsonb)
a - jsonb object/array
  b - jsonb object/array/value
  If a is jsonb object then b should be jsonb object to.

• jsonb_deep_extend(a jsonb, b jsonb)
a - jsonb object
  b - jsonb object

Usage examples

Concat arrays:

select jsonb_extend('[1]'::jsonb, '[2]'::jsonb);
 jsonb_extend 
--------------
 [1, 2]

Append a value to array:

select jsonb_extend('[1]'::jsonb, '2'::jsonb);
 jsonb_extend 
--------------
 [1, 2]

select jsonb_extend('[1]'::jsonb, '{"a": 2}'::jsonb);
jsonb_extend  
---------------
[1, {"a": 2}]

Merging two objects

SELECT jsonb_extend('{"a": 5, "b": 6}'::jsonb, '{"b": 7, "c": 9}'::jsonb) AS new_jsonb;
        new_jsonb
--------------------------
 {"a": 5, "b": 7, "c": 9}

SELECT jsonb_extend('{"a": {"b": 6}}'::jsonb, '{"a": {"c": 7}}'::jsonb) AS new_jsonb;
           new_jsonb
---------------------------------
{"a": {"c": 7}}

SELECT jsonb_deep_extend(false, '{"a": {"b": 6}}'::jsonb, '{"a": {"c": 7}}'::jsonb) AS new_jsonb;
        new_jsonb
-------------------------
 {"a": {"b": 6, "c": 7}}

Installation

1. Clone source:

git clone https://github.com/koctep/jsonb-extend.git
cd jsonb-extend

2. Build and install:

make USE_PGXS=1
make USE_PGXS=1 install

3. Enable jsonb_extend extension for your database:

CREATE EXTENSION jsonb_extend;

Building a debian package (example for Ubuntu Linux 14.04)

Instead of step 2 do:

1. Add official PostgreSQL repository to your system if necessary.

2. Install required dependencies for build:

   sudo apt-get install git debhelper postgresql-server-dev-9.4 devscripts
   

3. Build a package:

   debuild -i -us -uc -b
   

4. Generated .deb will be placed in parent directory. You may install it with command like:

   dpkg -i ../postgresql-9.4-jsonb-extend_1.0-1_amd64.deb