Introduce jsonb, a structured format for storing json.

The new format accepts exactly the same data as the json type. However, it is
stored in a format that does not require reparsing the orgiginal text in order
to process it, making it much more suitable for indexing and other operations.
Insignificant whitespace is discarded, and the order of object keys is not
preserved. Neither are duplicate object keys kept - the later value for a given
key is the only one stored.

The new type has all the functions and operators that the json type has,
with the exception of the json generation functions (to_json, json_agg etc.)
and with identical semantics. In addition, there are operator classes for
hash and btree indexing, and two classes for GIN indexing, that have no
equivalent in the json type.

This feature grew out of previous work by Oleg Bartunov and Teodor Sigaev, which
was intended to provide similar facilities to a nested hstore type, but which
in the end proved to have some significant compatibility issues.

Authors: Oleg Bartunov,  Teodor Sigaev, Peter Geoghegan and Andrew Dunstan.
Review: Andres Freund

4 files changed, 743 insertions, 208 deletions

diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
index ac285ce0119..cc458b4753f 100644
--- a/doc/src/sgml/datatype.sgml
+++ b/doc/src/sgml/datatype.sgml
@@ -139,7 +139,13 @@
       <row>
        <entry><type>json</type></entry>
        <entry></entry>
-       <entry>JSON data</entry>
+       <entry>textual JSON data</entry>
+      </row>
+
+      <row>
+       <entry><type>jsonb</type></entry>
+       <entry></entry>
+       <entry>binary JSON data, decomposed</entry>
       </row>
 
       <row>
@@ -4220,34 +4226,7 @@ SET xmloption TO { DOCUMENT | CONTENT };
    </sect2>
   </sect1>
 
-  <sect1 id="datatype-json">
-   <title><acronym>JSON</> Type</title>
-
-   <indexterm zone="datatype-json">
-    <primary>JSON</primary>
-   </indexterm>
-
-   <para>
-    The <type>json</type> data type can be used to store JSON (JavaScript
-    Object Notation) data, as specified in <ulink
-    url="http://www.ietf.org/rfc/rfc4627.txt">RFC 4627</ulink>.  Such
-    data can also be stored as <type>text</type>, but the
-    <type>json</type> data type has the advantage of checking that each
-    stored value is a valid JSON value.  There are also related support
-    functions available; see <xref linkend="functions-json">.
-   </para>
-
-   <para>
-    <productname>PostgreSQL</productname> allows only one server encoding
-    per database.  It is therefore not possible for JSON to conform rigidly
-    to the specification unless the server encoding is UTF-8.  Attempts to
-    directly include characters which cannot be represented in the server
-    encoding will fail; conversely, characters which can be represented in
-    the server encoding but not in UTF-8 will be allowed.
-    <literal>\uXXXX</literal> escapes are allowed regardless of the server
-    encoding, and are checked only for syntactic correctness.
-   </para>
-  </sect1>
+  &json;
 
   &array;
 
diff --git a/doc/src/sgml/filelist.sgml b/doc/src/sgml/filelist.sgml
index 6c8e254a584..ab6fcf7838c 100644
--- a/doc/src/sgml/filelist.sgml
+++ b/doc/src/sgml/filelist.sgml
@@ -22,6 +22,7 @@
 <!ENTITY dml        SYSTEM "dml.sgml">
 <!ENTITY func       SYSTEM "func.sgml">
 <!ENTITY indices    SYSTEM "indices.sgml">
+<!ENTITY json       SYSTEM "json.sgml">
 <!ENTITY mvcc       SYSTEM "mvcc.sgml">
 <!ENTITY perform    SYSTEM "perform.sgml">
 <!ENTITY queries    SYSTEM "queries.sgml">
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 71b9829d852..4e2fff7cd74 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -10079,12 +10079,13 @@ table2-mapping
   </indexterm>
 
    <para>
-   <xref linkend="functions-json-op-table"> shows the operators that are
-   available for use with JSON (see <xref linkend="datatype-json">) data.
+   <xref linkend="functions-json-op-table"> shows the operators that
+   are available for use with the two JSON datatypes (see <xref
+   linkend="datatype-json">).
   </para>
 
   <table id="functions-json-op-table">
-     <title>JSON Operators</title>
+     <title><type>json</> and <type>jsonb</> Operators</title>
      <tgroup cols="4">
       <thead>
        <row>
@@ -10121,13 +10122,13 @@ table2-mapping
        </row>
        <row>
         <entry><literal>#&gt;</literal></entry>
-        <entry>array of text</entry>
+        <entry>text[]</entry>
         <entry>Get JSON object at specified path</entry>
         <entry><literal>'{"a":[1,2,3],"b":[4,5,6]}'::json#&gt;'{a,2}'</literal></entry>
        </row>
        <row>
         <entry><literal>#&gt;&gt;</literal></entry>
-        <entry>array of text</entry>
+        <entry>text[]</entry>
         <entry>Get JSON object at specified path as text</entry>
         <entry><literal>'{"a":[1,2,3],"b":[4,5,6]}'::json#&gt;&gt;'{a,2}'</literal></entry>
        </row>
@@ -10135,13 +10136,107 @@ table2-mapping
      </tgroup>
    </table>
 
+  <note>
+   <para>
+    There are parallel variants of these operators for both the
+    <type>json</type> and <type>jsonb</type> types.  In addition to
+    those operators common to both types, a further set of operators
+    exists for <type>jsonb</type> (which comprise the default
+    <acronym>GIN</acronym> operator class).
+   </para>
+  </note>
   <para>
-   <xref linkend="functions-json-table"> shows the functions that are available
-   for creating and manipulating JSON (see <xref linkend="datatype-json">) data.
+   The following are <type>jsonb</>-only operators, used by
+   <type>jsonb</> operator classes.  For a full description of
+   <type>jsonb</> containment semantics and nesting, see <xref
+   linkend="json-containment">.  <xref linkend="json-indexing">
+   describes how these operators can be used to effectively index
+   <type>jsonb</>.
   </para>
+  <table id="functions-jsonb-op-table">
+     <title>Additonal JSONB Operators</title>
+     <tgroup cols="4">
+      <thead>
+       <row>
+        <entry>Operator</entry>
+        <entry>Right Operand Type</entry>
+        <entry>Description</entry>
+        <entry>Example</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><literal>=</literal></entry>
+        <entry>jsonb</entry>
+        <entry>Is the jsonb equal to this jsonb?</entry>
+        <entry><literal>'[1,2,3]'::jsonb = '[1,2,3]'::jsonb</literal></entry>
+       </row>
+       <row>
+        <entry><literal>@&gt;</literal></entry>
+        <entry>jsonb</entry>
+        <entry>Does the jsonb contain within it this jsonb?</entry>
+        <entry><literal>'{"a":1, "b":2}'::jsonb &#64;&gt; '{"b":2}'::jsonb</literal></entry>
+       </row>
+       <row>
+        <entry><literal>&lt;@</literal></entry>
+        <entry>jsonb</entry>
+        <entry>Does the jsonb have contained within it this jsonb?</entry>
+        <entry><literal>'{"b":2}'::jsonb &lt;@ '{"a":1, "b":2}'::jsonb</literal></entry>
+       </row>
+       <row>
+        <entry><literal>?</literal></entry>
+        <entry>text</entry>
+        <entry>Does this key/element <emphasis>string</emphasis> exist?</entry>
+        <entry><literal>'{"a":1, "b":2}'::jsonb ? 'b'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>?|</literal></entry>
+        <entry>text[]</entry>
+        <entry>Do any of these key/element <emphasis>strings</emphasis> exist?</entry>
+        <entry><literal>'{"a":1, "b":2, "c":3}'::jsonb ?| array['b', 'c']</literal></entry>
+       </row>
+       <row>
+        <entry><literal>?&amp;</literal></entry>
+        <entry>text[]</entry>
+        <entry>Do all of these key/element <emphasis>strings</emphasis> exist?</entry>
+        <entry><literal>'["a", "b"]'::jsonb ?&amp; array['a', 'b']</literal></entry>
+       </row>
+      </tbody>
+     </tgroup>
+   </table>
+
+  <!--
+     The release notes contain a reference to "functions-json-table". Since
+     that table is now split in two, the id has been parked here so we don't
+     have to change the release notes.
+  -->
+  <para id="functions-json-table">
+   <xref linkend="functions-json-creation-table"> shows the functions that are
+   available for creating <type>json</type> values.
+   (see <xref linkend="datatype-json">)
+  </para>
+
+  <indexterm>
+   <primary>array_to_json</primary>
+  </indexterm>
+  <indexterm>
+   <primary>row_to_json</primary>
+  </indexterm>
+  <indexterm>
+   <primary>to_json</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_build_array</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_build_object</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_object</primary>
+  </indexterm>
 
-  <table id="functions-json-table">
-    <title>JSON Support Functions</title>
+  <table id="functions-json-creation-table">
+    <title>JSON Creation Functions</title>
     <tgroup cols="5">
      <thead>
       <row>
@@ -10155,9 +10250,6 @@ table2-mapping
      <tbody>
       <row>
        <entry>
-         <indexterm>
-          <primary>array_to_json</primary>
-         </indexterm>
          <literal>array_to_json(anyarray [, pretty_bool])</literal>
        </entry>
        <entry><type>json</type></entry>
@@ -10171,9 +10263,6 @@ table2-mapping
       </row>
       <row>
        <entry>
-         <indexterm>
-          <primary>row_to_json</primary>
-         </indexterm>
          <literal>row_to_json(record [, pretty_bool])</literal>
        </entry>
        <entry><type>json</type></entry>
@@ -10186,9 +10275,6 @@ table2-mapping
       </row>
       <row>
        <entry>
-         <indexterm>
-          <primary>to_json</primary>
-         </indexterm>
          <literal>to_json(anyelement)</literal>
        </entry>
        <entry><type>json</type></entry>
@@ -10204,11 +10290,180 @@ table2-mapping
       </row>
       <row>
        <entry>
-         <indexterm>
-          <primary>json_array_length</primary>
-         </indexterm>
-         <literal>json_array_length(json)</literal>
+         <literal>json_build_array(VARIADIC "any")</literal>
        </entry>
+       <entry><type>json</type></entry>
+       <entry>
+         Builds a heterogeneously-typed json array out of a variadic argument list.
+       </entry>
+       <entry><literal>SELECT json_build_array(1,2,'3',4,5);</literal></entry>
+       <entry>
+<programlisting>
+ json_build_array
+-------------------
+ [1, 2, "3", 4, 5]
+ </programlisting>
+       </entry>
+      </row>
+      <row>
+       <entry>
+         <literal>json_build_object(VARIADIC "any")</literal>
+       </entry>
+       <entry><type>json</type></entry>
+       <entry>
+         Builds a JSON array out of a variadic argument list.  By
+         convention, the object is constructed out of alternating
+         name/value arguments.
+       </entry>
+       <entry><literal>SELECT json_build_object('foo',1,'bar',2);</literal></entry>
+       <entry>
+<programlisting>
+   json_build_object
+------------------------
+ {"foo" : 1, "bar" : 2}
+ </programlisting>
+       </entry>
+      </row>
+      <row>
+       <entry>
+         <literal>json_object(text[])</literal>
+       </entry>
+       <entry><type>json</type></entry>
+       <entry>
+         Builds a JSON object out of a text array.  The array must have either
+         exactly one dimension with an even number of members, in which case
+         they are taken as alternating name/value pairs, or two dimensions
+         such that each inner array has exactly two elements, which
+         are taken as a name/value pair.
+       </entry>
+       <entry><literal>select * from json_object('{a, 1, b, "def", c, 3.5}')  or <literal>select json_object('{{a, 1},{b, "def"},{c, 3.5}}')</literal></literal></entry>
+       <entry>
+<programlisting>
+              json_object
+---------------------------------------
+ {"a" : "1", "b" : "def", "c" : "3.5"}
+ </programlisting>
+       </entry>
+      </row>
+      <row>
+       <entry>
+         <literal>json_object(keys text[], values text[])</literal>
+       </entry>
+       <entry><type>json</type></entry>
+       <entry>
+         The two-argument form of JSON object takes keys and values pairwise from two separate
+         arrays. In all other respects it is identical to the one-argument form.
+       </entry>
+       <entry><literal>select json_object('{a, b}', '{1,2}');</literal></entry>
+       <entry>
+<programlisting>
+      json_object
+------------------------
+ {"a" : "1", "b" : "2"}
+ </programlisting>
+       </entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+
+  <para>
+   <xref linkend="functions-json-processing-table"> shows the functions that
+   are available for processing <type>json</type> and <type>jsonb</type> values.
+   (see <xref linkend="datatype-json">)
+  </para>
+
+  <indexterm>
+   <primary>json_array_length</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_array_length</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_each</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_each</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_each_text</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_each_text</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_extract_path</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_extract_path</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_extract_path_text</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_extract_path_text</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_object_keys</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_object_keys</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_populate_record</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_populate_record</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_populate_recordset</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_populate_recordset</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_array_elements</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_array_elements</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_array_elements_text</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_array_elements_text</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_typeof</primary>
+  </indexterm>
+  <indexterm>
+   <primary>jsonb_typeof</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_to_record</primary>
+  </indexterm>
+  <indexterm>
+   <primary>json_to_recordset</primary>
+  </indexterm>
+
+  <table id="functions-json-processing-table">
+    <title>JSON Processing Functions</title>
+    <tgroup cols="5">
+     <thead>
+      <row>
+       <entry>Function</entry>
+       <entry>Return Type</entry>
+       <entry>Description</entry>
+       <entry>Example</entry>
+       <entry>Example Result</entry>
+      </row>
+     </thead>
+     <tbody>
+      <row>
+       <entry><para><literal>json_array_length(json)</literal>
+         </para><para><literal>jsonb_array_length(jsonb)</literal>
+       </para></entry>
        <entry><type>int</type></entry>
        <entry>
          Returns the number of elements in the outermost JSON array.
@@ -10217,13 +10472,12 @@ table2-mapping
        <entry><literal>5</literal></entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_each</primary>
-         </indexterm>
-         <literal>json_each(json)</literal>
-       </entry>
-       <entry><type>SETOF key text, value json</type></entry>
+       <entry><para><literal>json_each(json)</literal>
+         </para><para><literal>jsonb_each(jsonb)</literal>
+       </para></entry>
+       <entry><para><literal>SETOF key text, value json</literal>
+         </para><para><literal>SETOF key text, value jsonb</literal>
+       </para></entry>
        <entry>
          Expands the outermost JSON object into a set of key/value pairs.
        </entry>
@@ -10238,12 +10492,9 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_each_text</primary>
-         </indexterm>
-         <literal>json_each_text(from_json json)</literal>
-       </entry>
+       <entry><para><literal>json_each_text(from_json json)</literal>
+         </para><para><literal>jsonb_each_text(from_json jsonb)</literal>
+       </para></entry>
        <entry><type>SETOF key text, value text</type></entry>
        <entry>
          Expands the outermost JSON object into a set of key/value pairs. The
@@ -10260,13 +10511,11 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_extract_path</primary>
-         </indexterm>
-         <literal>json_extract_path(from_json json, VARIADIC path_elems text[])</literal>
-       </entry>
-       <entry><type>json</type></entry>
+       <entry><para><literal>json_extract_path(from_json json, VARIADIC path_elems text[])</literal>
+        </para><para><literal>jsonb_extract_path(from_jsonb jsonb, VARIADIC path_elems text[])</literal>
+       </para></entry>
+       <entry><para><type>json</type></para><para><type>jsonb</type>
+       </para></entry>
        <entry>
          Returns JSON value pointed to by <parameter>path_elems</parameter>.
        </entry>
@@ -10274,12 +10523,9 @@ table2-mapping
        <entry><literal>{"f5":99,"f6":"foo"}</literal></entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_extract_path_text</primary>
-         </indexterm>
-         <literal>json_extract_path_text(from_json json, VARIADIC path_elems text[])</literal>
-       </entry>
+       <entry><para><literal>json_extract_path_text(from_json json, VARIADIC path_elems text[])</literal>
+         </para><para><literal>json_extract_path_text(from_json json, VARIADIC path_elems text[])</literal>
+       </para></entry>
        <entry><type>text</type></entry>
        <entry>
          Returns JSON value pointed to by <parameter>path_elems</parameter>.
@@ -10288,12 +10534,9 @@ table2-mapping
        <entry><literal>foo</literal></entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_object_keys</primary>
-         </indexterm>
-         <literal>json_object_keys(json)</literal>
-       </entry>
+       <entry><para><literal>json_object_keys(json)</literal>
+         </para><para><literal>jsonb_object_keys(jsonb)</literal>
+       </para></entry>
        <entry><type>SETOF text</type></entry>
        <entry>
           Returns set of keys in the JSON object.  Only the <quote>outer</quote> object will be displayed.
@@ -10309,18 +10552,16 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_populate_record</primary>
-         </indexterm>
-         <literal>json_populate_record(base anyelement, from_json json, [, use_json_as_text bool=false]</literal>
-       </entry>
+       <entry><para><literal>json_populate_record(base anyelement, from_json json, [, use_json_as_text bool=false])</literal>
+         </para><para><literal>jsonb_populate_record(base anyelement, from_json jsonb, [, use_json_as_text bool=false])</literal>
+       </para></entry>
        <entry><type>anyelement</type></entry>
        <entry>
          Expands the object in <replaceable>from_json</replaceable> to a row whose columns match
          the record type defined by base. Conversion will be best
          effort; columns in base with no corresponding key in <replaceable>from_json</replaceable>
-         will be left null. If a column is specified more than once, the last value is used.
+         will be left null. When processing <type>json</type>, if a
+         column is specified more than once, the last value is used.
        </entry>
        <entry><literal>select * from json_populate_record(null::x, '{"a":1,"b":2}')</literal></entry>
        <entry>
@@ -10332,19 +10573,17 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_populate_recordset</primary>
-         </indexterm>
-         <literal>json_populate_recordset(base anyelement, from_json json, [, use_json_as_text bool=false]</literal>
-       </entry>
+       <entry><para><literal>json_populate_recordset(base anyelement, from_json json, [, use_json_as_text bool=false])</literal>
+         </para><para><literal>jsonb_populate_recordset(base anyelement, from_json jsonb, [, use_json_as_text bool=false])</literal>
+       </para></entry>
        <entry><type>SETOF anyelement</type></entry>
        <entry>
          Expands the outermost set of objects in <replaceable>from_json</replaceable> to a set
          whose columns match the record type defined by base.
          Conversion will be best effort; columns in base with no
          corresponding key in <replaceable>from_json</replaceable> will be left null.
-         If a column is specified more than once, the last value is used.
+         When processing <type>json</type>, if a column is specified more
+         than once, the last value is used.
        </entry>
        <entry><literal>select * from json_populate_recordset(null::x, '[{"a":1,"b":2},{"a":3,"b":4}]')</literal></entry>
        <entry>
@@ -10357,13 +10596,12 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_array_elements</primary>
-         </indexterm>
-         <literal>json_array_elements(json)</literal>
-       </entry>
-       <entry><type>SETOF json</type></entry>
+       <entry><para><literal>json_array_elements(json)</literal>
+         </para><para><literal>jsonb_array_elements(jsonb)</literal>
+       </para></entry>
+       <entry><para><type>SETOF json</type>
+         </para><para><type>SETOF jsonb</type>
+       </para></entry>
        <entry>
          Expands a JSON array to a set of JSON values.
        </entry>
@@ -10379,12 +10617,9 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_array_elements_text</primary>
-         </indexterm>
-         <literal>json_array_elements_text(json)</literal>
-       </entry>
+       <entry><para><literal>json_array_elements_text(json)</literal>
+         </para><para><literal>jsonb_array_elements_text(jsonb)</literal>
+       </para></entry>
        <entry><type>SETOF text</type></entry>
        <entry>
          Expands a JSON array to a set of text values.
@@ -10400,12 +10635,9 @@ table2-mapping
        </entry>
       </row>
       <row>
-       <entry>
-         <indexterm>
-          <primary>json_typeof</primary>
-         </indexterm>
-         <literal>json_typeof(json)</literal>
-       </entry>
+       <entry><para><literal>json_typeof(json)</literal>
+         </para><para><literal>jsonb_typeof(jsonb)</literal>
+       </para></entry>
        <entry><type>text</type></entry>
        <entry>
          Returns the type of the outermost JSON value as a text string.  The types are
@@ -10418,98 +10650,11 @@ table2-mapping
       </row>
       <row>
        <entry>
-         <indexterm>
-          <primary>json_build_array</primary>
-         </indexterm>
-         <literal>json_build_array(VARIADIC "any")</literal>
-       </entry>
-       <entry><type>json</type></entry>
-       <entry>
-         Builds a heterogeneously-typed json array out of a variadic argument list.
-       </entry>
-       <entry><literal>SELECT json_build_array(1,2,'3',4,5);</literal></entry>
-       <entry>
-<programlisting>
- json_build_array
--------------------
- [1, 2, "3", 4, 5]
- </programlisting>
-       </entry>
-      </row>
-      <row>
-       <entry>
-         <indexterm>
-          <primary>json_build_object</primary>
-         </indexterm>
-         <literal>json_build_object(VARIADIC "any")</literal>
-       </entry>
-       <entry><type>json</type></entry>
-       <entry>
-         Builds a JSON array out of a variadic argument list.
-         By convention, the object is 
-         constructed out of alternating name/value arguments.
-       </entry>
-       <entry><literal>SELECT json_build_object('foo',1,'bar',2);</literal></entry>
-       <entry>
-<programlisting>
-   json_build_object
-------------------------
- {"foo" : 1, "bar" : 2}
- </programlisting>
-       </entry>
-      </row>
-      <row>
-       <entry>
-         <indexterm>
-          <primary>json_object</primary>
-         </indexterm>
-         <literal>json_object(text[])</literal>
-       </entry>
-       <entry><type>json</type></entry>
-       <entry>
-         Builds a JSON object out of a text array.  The array must have either
-         exactly one dimension with an even number of members, in which case
-         they are taken as alternating name/value pairs, or two dimensions
-         such that each inner array has exactly two elements, which
-         are taken as a name/value pair.
-       </entry>
-       <entry><literal>select * from json_object('{a, 1, b, "def", c, 3.5}')  or <literal>select * from json_object('{{a, 1},{b, "def"},{c, 3.5}}')</literal></literal></entry>
-       <entry>
-<programlisting>
-              json_object
----------------------------------------
- {"a" : "1", "b" : "def", "c" : "3.5"}
- </programlisting>
-       </entry>
-      </row>
-      <row>
-       <entry>
-         <literal>json_object(keys text[], values text[])</literal>
-       </entry>
-       <entry><type>json</type></entry>
-       <entry>
-         The two-argument form of JSON object takes keys and values pairwise from two separate
-         arrays. In all other respects it is identical to the one-argument form.
-       </entry>
-       <entry><literal>select * from json_object('{a, b}', '{1,2}');</literal></entry>
-       <entry>
-<programlisting>
-      json_object
-------------------------
- {"a" : "1", "b" : "2"}
- </programlisting>
-       </entry>
-      </row>
-      <row>
-       <entry>
-         <indexterm>
-          <primary>json_to_record</primary>
-         </indexterm>
          <literal>json_to_record(json, nested_as_text bool)</literal>
        </entry>
        <entry><type>record</type></entry>
        <entry>
-         json_to_record returns an arbitrary record from a JSON object.  As with all functions 
+         Returns an arbitrary record from a JSON object.  As with all functions 
          returning 'record', the caller must explicitly define the structure of the record 
          when making the call. The input JSON must be an object, not a scalar or an array.
          If nested_as_text is true, the function coerces nested complex elements to text.
@@ -10526,14 +10671,11 @@ table2-mapping
       </row>
       <row>
        <entry>
-         <indexterm>
-          <primary>json_to_recordset</primary>
-         </indexterm>
          <literal>json_to_recordset(json, nested_as_text bool)</literal>
        </entry>
        <entry><type>setof record</type></entry>
        <entry>
-         json_to_recordset returns an arbitrary set of records from a JSON object.  As with 
+         Returns an arbitrary set of records from a JSON object.  As with 
          json_to_record, the structure of the record must be explicitly defined when making the
          call.  However, with json_to_recordset the input JSON must be an array containing 
          objects.  nested_as_text works as with json_to_record.
diff --git a/doc/src/sgml/json.sgml b/doc/src/sgml/json.sgml
new file mode 100644
index 00000000000..d7d6de8d287
--- /dev/null
+++ b/doc/src/sgml/json.sgml
@@ -0,0 +1,413 @@
+<!-- doc/src/sgml/json.sgml -->
+
+<sect1 id="datatype-json">
+ <title><acronym>JSON</> Types</title>
+
+ <indexterm zone="datatype-json">
+  <primary>JSON</primary>
+ </indexterm>
+
+ <indexterm zone="datatype-json">
+  <primary>JSONB</primary>
+ </indexterm>
+
+ <para>
+  JSON data types are for storing JSON (JavaScript Object Notation)
+  data, as specified in <ulink url="http://rfc7159.net/rfc7159">RFC
+  7159</ulink>. Such data can also be stored as <type>text</type>, but
+  both JSON data types have the advantage of enforcing that each
+  stored value is a valid JSON value.  There are also related support
+  functions available; see <xref linkend="functions-json">.
+ </para>
+
+ <para>
+  There are two JSON data types: <type>json</> and <type>jsonb</>.
+  Both accept <emphasis>almost</emphasis> identical sets of values as
+  input.  The major practical difference is one of efficiency.  The
+  <type>json</> data type stores an exact copy of the the input text,
+  which processing functions must continually reparse, while
+  <type>jsonb</> data is stored in a decomposed binary format that
+  makes it slightly less efficient to input due to added serialization
+  overhead, but significantly faster to process, since it never needs
+  reparsing.  <type>jsonb</> also supports advanced
+  <acronym>GIN</acronym> indexing, which is a further significant
+  advantage.
+ </para>
+
+ <para>
+  The other difference between the types is that the <type>json</>
+  type is guaranteed to contain an exact copy of the input, including
+  preservation of semantically insignificant white space, and the
+  order of keys within JSON objects (although <type>jsonb</> will
+  preserve trailing zeros within a JSON number). Also, because the
+  exact text is kept, if a JSON object within the value contains the
+  same key more than once, and has been stored using the <type>json</>
+  type, all the key/value pairs are kept.  In that case, the
+  processing functions consider the last value as the operative one.
+  By contrast, <type>jsonb</> does not preserve white space, does not
+  preserve the order of object keys, and does not keep duplicate
+  object keys.  Only the last value for a key specified in the input
+  is kept.
+ </para>
+
+ <para>
+  In general, most applications will prefer to store JSON data as
+  <type>jsonb</>, unless there are quite specialized needs.
+ </para>
+
+ <para>
+  <productname>PostgreSQL</productname> allows only one server
+  encoding per database.  It is therefore not possible for the JSON
+  types to conform rigidly to the specification unless the server
+  encoding is UTF-8. Attempts to directly include characters which
+  cannot be represented in the server encoding will fail; conversely,
+  characters which can be represented in the server encoding but not
+  in UTF-8 will be allowed.  <literal>\uXXXX</literal> escapes are
+  allowed regardless of the server encoding, and are checked only for
+  syntactic correctness.
+ </para>
+
+ <sect2 id="json-types">
+  <title>Mapping of RFC-7159/JSON Primitive Types to <productname>PostgreSQL</productname> Types</title>
+  <table id="json-type-mapping-table">
+     <title>Mapping of type correspondence, notes</title>
+     <tgroup cols="3">
+      <thead>
+       <row>
+        <entry><productname>PostgreSQL</productname> type</entry>
+        <entry>RFC-7159/JSON primitive type</entry>
+        <entry>Notes</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><type>text</></entry>
+        <entry><type>string</></entry>
+        <entry>See general introductory notes on encoding and JSON</entry>
+       </row>
+       <row>
+        <entry><type>numeric</></entry>
+        <entry><type>number</></entry>
+        <entry><literal>NaN</literal> and <literal>infinity</literal> values are disallowed</entry>
+       </row>
+       <row>
+        <entry><type>boolean</></entry>
+        <entry><type>boolean</></entry>
+        <entry>Only lowercase <literal>true</literal> and <literal>false</literal> values are accepted</entry>
+       </row>
+       <row>
+        <entry><type>unknown</></entry>
+        <entry><type>null</></entry>
+        <entry>SQL <literal>NULL</literal> is orthogonal.  NULL semantics do not apply.</entry>
+       </row>
+      </tbody>
+     </tgroup>
+   </table>
+  <para>
+    Primitive types described by <acronym>RFC</> 7159 are effectively
+    internally mapped onto native
+    <productname>PostgreSQL</productname> types.  Therefore, there are
+    some very minor additional constraints on what constitutes valid
+    <type>jsonb</type> that do not apply to the <type>json</type>
+    type, or to JSON in the abstract, that pertain to limits on what
+    can be represented by the underlying type system.  These
+    implementation-defined restrictions are permitted by
+    <acronym>RFC</> 7159.  However, in practice problems are far more
+    likely to occur in other implementations which internally
+    represent the <type>number</> JSON primitive type as IEEE 754
+    double precision floating point values, which <acronym>RFC</> 7159
+    explicitly anticipates and allows for.  When using JSON as an
+    interchange format with such systems, the danger of losing numeric
+    precision in respect of data originally stored by
+    <productname>PostgreSQL</productname> should be considered.
+  </para>
+  <para>
+    Conversely, as noted above there are some minor restrictions on
+    the input format of JSON primitive types that do not apply to
+    corresponding <productname>PostgreSQL</productname> types.
+  </para>
+
+ </sect2>
+
+ <sect2 id="json-querying">
+  <title>Querying <type>jsonb</type> documents effectively</title>
+  <para>
+   Representing data as JSON can be considerably more flexible than
+   the traditional relational data model, which is compelling in
+   environments where requirements are fluid.  It is quite possible
+   for both approaches to co-exist and complement each other within
+   the same application.  However, even for applications where maximal
+   flexibility is desired, it is still recommended that JSON documents
+   have a somewhat fixed structure.  This structure is typically
+   unenforced (though enforcing some business rules declaratively is
+   possible), but makes it easier to write queries that usefully
+   summarize a set of <quote>documents</> (datums) in a table.
+  </para>
+  <para>
+   <type>jsonb</> data is subject to the same concurrency control
+   considerations as any other datatype when stored in a table.
+   Although storing large documents is practicable, in order to ensure
+   correct behavior row-level locks are, quite naturally, aquired as
+   rows are updated.  Consider keeping <type>jsonb</> documents at a
+   manageable size in order to decrease lock contention among updating
+   transactions.  Ideally, <type>jsonb</> documents should each
+   represent an atomic datum that business rules dictate cannot
+   reasonably be further subdivided into smaller atomic datums that
+   can be independently modified.
+  </para>
+ </sect2>
+ <sect2 id="json-keys-elements">
+  <title><type>jsonb</> Input and Output Syntax</title>
+  <para>
+   In effect, <type>jsonb</> has an internal type system whose
+   implementation is defined in terms of several particular ordinary
+   <productname>PostgreSQL</productname> types.  The SQL parser does
+   not have direct knowledge of the internal types that constitute a
+   <type>jsonb</>.
+  </para>
+  <para>
+   The following are all valid <type>jsonb</> expressions:
+  <programlisting>
+-- Simple scalar/primitive value (explicitly required by RFC-7159)
+SELECT '5'::jsonb;
+
+-- Array of heterogeneous, primitive-typed elements
+SELECT '[1, 2, "foo", null]'::jsonb;
+
+-- Object of heterogeneous key/value pairs of primitive types
+-- Note that key values are always strings
+SELECT '{"bar": "baz", "balance": 7.77, "active":false}'::jsonb;
+  </programlisting>
+  </para>
+  <para>
+   Note the distinction between scalar/primitive values as elements,
+   keys and values.
+  </para>
+ </sect2>
+ <sect2 id="json-containment">
+  <title><type>jsonb</> containment</title>
+  <indexterm>
+    <primary>jsonb</primary>
+    <secondary>containment</secondary>
+  </indexterm>
+  <para>
+    Testing <quote>containment</> is an important capability of
+    <type>jsonb</>.  There is no parallel set of facilities for the
+    <type>json</> type.  Containment is the ability to determine if
+    one <type>jsonb</> document has contained within it another one.
+    <type>jsonb</> is nested, and so containment semantics are nested;
+    technically, top-down, unordered <emphasis>subtree isomorphism</>
+    may be tested.  Containment is conventionally tested using the
+    <literal>@&gt;</> operator, which is made indexable by various
+    operator classes discussed later in this section.
+  </para>
+  <programlisting>
+-- Simple scalar/primitive values may contain only each other:
+SELECT '"foo"'::jsonb @> '"foo"'::jsonb;
+
+-- The array on the right hand side is contained within the one on the
+-- left hand side:
+SELECT '[1, 2, 3]'::jsonb @> '[1, 3]'::jsonb;
+
+-- The object with a single pair on the right hand side is contained
+-- within the object on the left hand side:
+SELECT '{"product": "PostgreSQL", "version": 9.4, "jsonb":true}'::jsonb @> '{"version":9.4}'::jsonb;
+
+-- The array on the right hand side is not contained within the array
+-- containing a nested array on the left hand side:
+SELECT '[1, 2, [1, 3]]'::jsonb @> '[1, 3]'::jsonb;
+
+-- But with a layer of nesting, it is:
+SELECT '[1, 2, [1, 3]]'::jsonb @> '[[1, 3]]'::jsonb;
+  </programlisting>
+  <para>
+    It is both a sufficient and a necessary condition for nesting
+    levels to <quote>line up</> for one <type>jsonb</> to contain
+    within it another.  Under this definition, objects and arrays
+    cannot <quote>line up</>, not least because objects contain
+    key/value pairs, while arrays contain elements.
+  </para>
+  <para>
+    As a special exception to the general principle that nesting
+    levels should <quote>line up</>, an array may contain a raw scalar:
+  </para>
+  <programlisting>
+-- This array contains the raw scalar value:
+SELECT '["foo", "bar"]'::jsonb @> '"bar"'::jsonb;
+-- The special exception is not reciprocated -- non-containment is indicated here:
+SELECT '"bar"'::jsonb @> '["bar"]'::jsonb;
+  </programlisting>
+  <para>
+    Objects are better suited for testing containment when there is a
+    great deal of nesting involved, because unlike arrays they are
+    internally optimized for searching, and do not need to be searched
+    linearly within a single <type>jsonb</> document.
+  </para>
+  <programlisting>
+-- The right-hand side object is contained in this example:
+SELECT '{"p":1, "a":{"b":3, "q":11}, "i":77}'::jsonb @> '{"a":{"b":3}}'::jsonb;
+  </programlisting>
+  <para>
+    The various containment operators, along with all other JSON
+    operators and support functions are documented fully within <xref
+    linkend="functions-json">, <xref
+    linkend="functions-jsonb-op-table">.
+  </para>
+ </sect2>
+ <sect2 id="json-indexing">
+  <title><type>jsonb</> GIN Indexing</title>
+  <indexterm>
+    <primary>jsonb</primary>
+    <secondary>indexes on</secondary>
+  </indexterm>
+  <para>
+    <type>jsonb</> GIN indexes can be used to efficiently search among
+    more than one possible key/value pair within a single
+    <type>jsonb</> datum/document, among a large number of such
+    documents within a column in a table (i.e. among many rows).
+  </para>
+  <para>
+    <type>jsonb</> has GIN index support for the <literal>@&gt;</>,
+    <literal>?</>, <literal>?&amp;</> and <literal>?|</> operators.
+    The default GIN operator class makes all these operators
+    indexable:
+  </para>
+  <programlisting>
+-- GIN index (default opclass)
+CREATE INDEX idxgin ON api USING GIN (jdoc);
+
+-- GIN jsonb_hash_ops index
+CREATE INDEX idxginh ON api USING GIN (jdoc jsonb_hash_ops);
+  </programlisting>
+  <para>
+    The non-default GIN operator class <literal>jsonb_hash_ops</>
+    supports indexing the <literal>@&gt;</> operator only.
+  </para>
+  <para>
+    Consider the example of a table that stores JSON documents
+    retrieved from a third-party web service, with a documented schema
+    definition.  An example of a document retrieved from this web
+    service is as follows:
+    <programlisting>
+{
+    "guid": "9c36adc1-7fb5-4d5b-83b4-90356a46061a",
+    "name": "Angela Barton",
+    "is_active": true,
+    "company": "Magnafone",
+    "address": "178 Howard Place, Gulf, Washington, 702",
+    "registered": "2009-11-07T08:53:22 +08:00",
+    "latitude": 19.793713,
+    "longitude": 86.513373,
+    "tags": [
+        "enim",
+        "aliquip",
+        "qui"
+    ]
+}
+    </programlisting>
+    If a GIN index is created on the table that stores these
+    documents, <literal>api</literal>, on its <literal>jdoc</>
+    <type>jsonb</> column, we can expect that queries like the
+    following may make use of the index:
+    <programlisting>
+-- Note that both key and value have been specified
+SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc @&gt; '{"company": "Magnafone"}';
+    </programlisting>
+    However, the index could not be used for queries like the
+    following, due to the aforementioned nesting restriction:
+    <programlisting>
+SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc -> 'tags' ? 'qui';
+    </programlisting>
+    Still, with judicious use of expressional indexing, the above
+    query can use an index scan.  If there is a requirement to find
+    those records with a particular tag quickly, and the tags have a
+    high cardinality across all documents, defining an index as
+    follows is an effective approach to indexing:
+  <programlisting>
+-- Note that the "jsonb -> text" operator can only be called on an
+-- object, so as a consequence of creating this index the root "jdoc"
+-- datum must be an object.  This is enforced during insertion.
+CREATE INDEX idxgin ON api USING GIN ((jdoc -> 'tags'));
+  </programlisting>
+  </para>
+  <para>
+    Expressional indexes are discussed in <xref
+    linkend="indexes-expressional">.
+  </para>
+  <para>
+    For the most flexible approach in terms of what may be indexed,
+    sophisticated querying on nested structures is possible by
+    exploiting containment.  At the cost of having to create an index
+    on the entire structure for each row, and not just a nested
+    subset, we may exploit containment semantics to get an equivalent
+    result with a non-expressional index on the entire <quote>jdoc</>
+    column, <emphasis>without</> ever having to create additional
+    expressional indexes against the document (provided only
+    containment will be tested).  While the index will be considerably
+    larger than our expression index, it will also be much more
+    flexible, allowing arbitrary structured searching.  Such an index
+    can generally be expected to help with a query like the following:
+  </para>
+  <programlisting>
+SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc @&gt; '{"tags": ["qui"]}';
+  </programlisting>
+  <para>
+   For full details of the semantics that these indexable operators
+   implement, see <xref linkend="functions-json">, <xref
+   linkend="functions-jsonb-op-table">.
+  </para>
+ </sect2>
+ <sect2 id="json-opclass">
+  <title><type>jsonb</> non-default GIN operator class</title>
+  <indexterm>
+    <primary>jsonb</primary>
+    <secondary>indexes on</secondary>
+  </indexterm>
+  <para>
+    Although only the <literal>@&gt;</> operator is made indexable, a
+    <literal>jsonb_hash_ops</literal> operator class GIN index has
+    some notable advantages over an equivalent GIN index of the
+    default GIN operator class for <type>jsonb</type>.  Search
+    operations typically perform considerably better, and the on-disk
+    size of a <literal>jsonb_hash_ops</literal> operator class GIN
+    index can be much smaller.
+  </para>
+ </sect2>
+ <sect2 id="json-btree-indexing">
+  <title><type>jsonb</> B-Tree and hash indexing</title>
+  <para>
+    <type>jsonb</type> comparisons and related operations are
+    <emphasis>type-wise</>, in that the underlying
+    <productname>PostgreSQL</productname> datatype comparators are
+    invoked recursively, much like a traditional composite type.
+  </para>
+  <para>
+    <type>jsonb</> also supports <type>btree</> and <type>hash</>
+    indexes.  Ordering between <type>jsonb</> datums is:
+    <synopsis>
+      <replaceable>Object</replaceable> > <replaceable>Array</replaceable> > <replaceable>Boolean</replaceable> > <replaceable>Number</replaceable> > <replaceable>String</replaceable> > <replaceable>Null</replaceable>
+
+      <replaceable>Object with n pairs</replaceable> > <replaceable>object with n - 1 pairs</replaceable>
+
+      <replaceable>Array with n elements</replaceable> > <replaceable>array with n - 1 elements</replaceable>
+    </synopsis>
+      Subsequently, individual primitive type comparators are invoked.
+      All comparisons of JSON primitive types occurs using the same
+      comparison rules as the underlying
+      <productname>PostgreSQL</productname> types.  Strings are
+      compared lexically, using the default database collation.
+      Objects with equal numbers of pairs are compared:
+    <synopsis>
+      <replaceable>key-1</replaceable>, <replaceable>value-1</replaceable>, <replaceable>key-2</replaceable> ...
+    </synopsis>
+      Note however that object keys are compared in their storage order, and in particular,
+      since shorter keys are stored before longer keys, this can lead to results that might be
+      unintuitive, such as:
+      <programlisting>{ "aa": 1, "c": 1} > {"b": 1, "d": 1}</programlisting>
+      Similarly, arrays with equal numbers of elements are compared:
+    <synopsis>
+      <replaceable>element-1</replaceable>, <replaceable>element-2</replaceable> ...
+    </synopsis>
+  </para>
+ </sect2>
+</sect1>