X-Git-Url: https://git.8kb.co.uk/?p=postgresql%2Fpg_jsonb_opx;a=blobdiff_plain;f=README.md;fp=README.md;h=b38e3155696b74d6488ef96cb58269c83dda297c;hp=1073f68b6c8a69ae2a4a9113d573a24a8ab129d2;hb=eeec9a82f053ea71be517d39ddc4c25fccfa5579;hpb=d7958daa16351c072af5fbd5d8522f10292e1aa3

diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -1,9 +1,113 @@
 jsonb_opx
 =========
 
-Test delete and concatenation operators for PostgreSQL 9.4
+Test delete and concatenation operators for PostgreSQL 9.4, this is purely for experimentation and contain errors and bad form.  
 
-This is purely experimentation and will contain many errors and bad form.
+**USE ON PRODUCTION SYSTEMS AT OWN RISK**
 
-**DO NOT USE ON PRODUCTION SYSTEMS**
+* delete operator **"-"** provided by functions *jsonb_delete(jsonb, text) jsonb_delete(jsonb, text[]) and jsonb_delete(jsonb, jsonb)*
+    Provides:
+        jsonb - text
+        jsonb - text[]
+        jsonb - jsonb
 
+    Note: When using text type operators on jsonb arrays only elements of type text will be deleted. E.g.
+
+```sql
+TEST=# SELECT '[1, "1", "2", 2]'::jsonb - '2'::text;
+  ?column?   
+-------------
+ [1, "1", 2]
+(1 row)
+
+TEST=# SELECT '[1, "1", "2", 2]'::jsonb - '"2"'::text;
+     ?column?     
+------------------
+ [1, "1", "2", 2]
+(1 row)
+
+TEST=# SELECT '[1, "1", "2", 2]'::jsonb - array['2']::text[];
+  ?column?   
+-------------
+ [1, "1", 2]
+(1 row)
+
+TEST=# SELECT '[1, "1", "2", 2]'::jsonb - array['"2"']::text[];
+     ?column?     
+------------------
+ [1, "1", "2", 2]
+(1 row)
+
+```
+
+    More. E.g.
+ 
+```sql
+TEST=# SELECT '{"a": 1, "b": 2, "c": 3}'::jsonb - 'b'::text;
+     ?column?     
+------------------
+ {"a": 1, "c": 3}
+(1 row)
+
+TEST=# SELECT '{"a": 1, "b": 2, "c": 3}'::jsonb - ARRAY['a','b'];
+ ?column? 
+----------
+ {"c": 3}
+(1 row)
+
+TEST=# SELECT '{"a": 1, "b": 2, "c": 3}'::jsonb - '{"a": 4, "b": 2}'::jsonb;
+     ?column?     
+------------------
+ {"a": 1, "c": 3}
+(1 row)
+
+TEST=# SELECT '{"a": 1, "b": 2, "c": 3, "d": {"a": 4}}'::jsonb - '{"d": {"a": 4}, "b": 2}'::jsonb;
+     ?column?     
+------------------
+ {"a": 1, "c": 3}
+(1 row)
+
+TEST=# SELECT '{"a": 4, "b": 2, "c": 3, "d": {"a": 4}}'::jsonb - '{"a": 4, "b": 2}'::jsonb;
+        ?column?         
+-------------------------
+ {"c": 3, "d": {"a": 4}}
+(1 row)
+```
+    
+* concatenation operator  **"||"** provided by function *jsonb_concat(jsonb, jsonb)*
+    Provides:
+         jsonb || jsonb
+
+    E.g.
+
+```sql
+TEST=#  SELECT '{"a": 1, "b": 2, "c": 3}'::jsonb || '{"a": 4, "b": 2, "d": 4}'::jsonb;
+             ?column?             
+----------------------------------
+ {"a": 4, "b": 2, "c": 3, "d": 4}
+(1 row)
+
+TEST=#  SELECT '["a", "b"]'::jsonb || '["c"]'::jsonb;
+    ?column?     
+-----------------
+ ["a", "b", "c"]
+(1 row)
+
+TEST=#  SELECT '[1,2,3]'::jsonb || '[3,4,5]'::jsonb;
+      ?column?      
+--------------------
+ [1, 2, 3, 3, 4, 5]
+(1 row)
+
+TEST=#  SELECT '{"a": 1, "b": 2, "c": 3}'::jsonb || '[1,2,3]'::jsonb;
+              ?column?               
+-------------------------------------
+ [{"a": 1, "b": 2, "c": 3}, 1, 2, 3]
+(1 row)
+
+TEST=#  SELECT '{"a": 1, "b": 2, "c": 3}'::jsonb || '[1,2,3]'::jsonb || '"a"'::jsonb;
+                 ?column?                 
+------------------------------------------
+ [{"a": 1, "b": 2, "c": 3}, 1, 2, 3, "a"]
+(1 row)
+```