Starting with JSON Path Expressions in Oracle 12.1.0.2

Manager, Product Management
• Server Technology, Oracle Corporation
• Oracle 25+ years experience
• XML Infrastructure products in Oracle's
Server Technology division

Management Consultant
• Ordina, The Netherlands
• Oracle 20+ years experience
• Oracle ACE Director (www.xmldb.nl)

Basic constructs
(recursive)
 Base values
number, string,
boolean, …
 Objects { }
sets of label-value
pairs
 Arrays [ ]
lists of values

New in Oracle Database 12.1.0.2.0
 Store and manage JSON documents in Database
▪ JSON documents stored as text
▪ JSON documents can be indexed
 Access JSON documents via developer-friendly
‘Document-Store’ API’s
 SQL query capabilities over JSON documents for
reporting and analysis

Allows Oracle RDBMS to be used as a JSON
Document Store
 Enables storing, indexing and querying of JSON
documents
No new JSON data type
IS JSON constraint used to ensure a column
contains valid JSON documents
 Apply to CLOB, VARCHAR2, RAWand BLOB data
 Enables use of .dotted notation to navigate JSON
document structure and access content

JSON data can also be
 Partitioned
 Used with Flashback
 Recovered (when proper backup is in place)
 Used with Securefile storage
▪ Smaller storage
▪ Encryption, Deduplication, Compressed
 Multiple index options
 Caching advantages, etc., etc.,…

JSON content is accessible from SQL via
new operators
JSON operators use JSON Path
language to navigate JSON objects
Proposed extention to SQL standards

The JSON Path language makes it possible to
address the contents of a JSON document
 A JSON path expression can address 1 of 4 items
▪ The entire object, a scalar value, an array, a specific object
 JSON Path expressions are similar to XPath
Expressions
▪ The entire document is referenced by $
▪ All JSON path expressions start with a $ symbol
▪ Key names are separated by a ’.’ (period)
JSON Path expressions are case sensitive

JSON Path Expression Type Contents
$.Reference String "ABULL-20120421"
$.ShippingInstructions.Address.zipcode Number 99236
$.ShippingInstructions.Address Object
{ "street": "200 Sporting Green",
"city": "South San Francisco",
"state": "CA",
"zipCode": 99236,
"country": “USA"
}
$LineItems Array
[ { "ItemNumber" : 1,
"Part" : {
"Description" : “Christmas”
"UPCCode" : 13131092899 }
},
{ "ItemNumber" : 2,
"Part" : {
"Description" : “Easter”
"UPCCode" : 13131092899 }
]

Compatible with Java Script
 $.phone[0]
Wildcards, Multi-Selects, Ranges
 $.phone[*], $.phone[0,1 5 to 9]
Predicates
 .address?(.zip > $zip)
SQL conversion functions usable in
predicates
 .?(to_date(.date) > $date)

JSON_VALUE
 Return a single scalar value from a JSON Document
JSON_QUERY
 Return a JSON Object or JSON Array from a JSON
Document
JSON_EXISTS
 Filter rows based on JSON-PATH expressions
JSON_TABLE
 Project in-line, nested relational views from JSON
Documents
JSON_TEXTCONTAINS
 JSON aware full-text searching of JSON Documents
Proposed extension to SQL standards

Using .dotted notation
SQL> select j.PO_DOCUMENT
2 from J_PURCHASEORDER j
3 where j.PO_DOCUMENT.PONumber = 1600
4 /
SQL> select j.PO_DOCUMENT.ShippingInstructions.Address
2 from J_PURCHASEORDER j
3 where j.PO_DOCUMENT.PONumber = 1600
4 /

Can only return a SCALAR value
SQL> select JSON_VALUE(PO_DOCUMENT,
2 '$.LineItems[0].Part.UnitPrice'
3 returning NUMBER(5,3))
4 from J_PURCHASEORDER p
5 where JSON_VALUE(PO_DOCUMENT,
6 '$.PONumber' returning NUMBER(10)) = 1600 ;

Can only returns anARRAY or OBJECT
SELECT JSON_QUERY('{a:100, b:200, c:300}', '$.*' WITH WRAPPER)
AS value
FROM DUAL;
VALUE
--------------------------------------------------------------------------------
[100,200,300]

Used in the WHERE clause
SQL> select count(*)
2 from J_PURCHASEORDER
3 where JSON_EXISTS( PO_DOCUMENT
4 , '$.ShippingInstructions.Address.state')
5 /

Used in the FROM clause
Creation of an inline relational view of JSON
SQL> SELECT m.*
2 FROM J_PURCHASEORDER p
3 , JSON_TABLE
4 ( p.PO_DOCUMENT, '$'
5 columns
6 po_rno FOR ORDINALITY,
7 po_number NUMBER(10) path '$.PONumber'
8 ) m
9 WHERE po_number > 1600 and PO_Number < 1605;

SQL> SELECT m.*
2 FROM J_PURCHASEORDER p
3 , JSON_TABLE
4 ( p.PO_DOCUMENT, '$'
5 columns
6 po_number NUMBER(10) path '$.PONumber',
7 reference VARCHAR2(30) path '$.Reference',
8 requestor VARCHAR2(32) path '$.Requestor',
9 userid VARCHAR2(10) path '$.User',
10 center VARCHAR2(16) path '$.CostCenter'
11 ) m
12 WHERE po_number > 1600 and PO_Number < 1605;

1 row output for each row in table
PO_NUMBER REFERENCE REQUSTOR USERID CENTER
1600 ABULL-20140421 Alexis Bull ABULL A50
1603 KCHUNG-20141022 Kelly Chung KCHUNG A50
1604 LBISSOT-20141009 Laura Bissot LBISSOT A50

create or replace view J_PURCHASEORDER_DETAIL_VIEW as
select d.*
from J_PURCHASEORDER p,
JSON_TABLE
(p.PO_DOCUMENT, '$'
columns (
PO_NUMBER NUMBER(10) path '$.PONumber',
USERID VARCHAR2(10) path '$.User',
COSTCENTER VARCHAR2(16) path '$.CostCenter',
NESTED PATH '$.LineItems[*]'
columns
( ITEMNO NUMBER(38) path '$.ItemNumber',
UNITPRICE NUMBER(14,2) path '$.Part.UnitPrice'
) ) ) d;

Full-text search of JSON data that is stored in
a VARCHAR2, BLOB, or CLOB column
Must be used in conjunction with special
JSON Oracle Text Index
Use CTXSYS.JSON_SECTION_GROUP

Check constraint guarantees that values are
valid JSON documents
IS [NOT] JSON predicate
 Returns TRUE if column value is JSON, FALSE
otherwise
 Full parse of the data while validating syntax
 Tolerant and strict modes
Use to ensure that the documents stored in a
column are valid JSON

LAX
 Default
STRICT
 Among others:
▪ JSON property (key) name and each string value must be enclosed
in double quotation marks (")
▪ Fractional numerals must have leading zero ( 0.14 | .14)
▪ XML DB Developers Guide or JSON Standards (ECMA-404 / 262)
 More performance intensive than Lax

create table J_PURCHASEORDER
( ID RAW(16) NOT NULL,
DATE_LOADED TIMESTAMP(6) WITH TIME ZONE,
PO_DOCUMENT CLOB
CHECK (PO_DOCUMENT IS JSON) )
insert into J_PURCHASEORDER values(‘0x1’,‘{Invalid JSON Text}');
ERROR at line 1:
ORA-02290: check constraint (DEMO.IS_VALID_JSON) violated

ALL_JSON_COLUMNS
DBA_JSON_COLUMNS
USER_JSON_COLUMNS
Will not show up when
 Check constraint combines condition IS JSON
with another condition using logical condition OR
 “jcol is json OR length(jcol) < 1000” ???

-- Default (lax)
SQL> SELECT json_column
2 FROM t
3 WHERE ( json_column IS JSON);
-- Explicit
SQL> SELECT json_column
2 FROM t
3 WHERE ( json_column IS JSON (STRICT));

SQL> insert into J_PURCHASEORDER
2 select SYS_GUID(),
3 SYSTIMESTAMP,
4 JSON_DOCUMENT
5 from STAGING_TABLE
6 where JSON_DOCUMENT IS JSON;
SQL> delete from STAGING_TABLE
2 where DOCUMENT IS NOT JSON;

NULL on ERROR
 The Default
 Return NULL instead of raising the error
ERROR on ERROR
 Raise the error (no special handling)
TRUE ON ERROR
 In JSON_EXISTS
 Return TRUE instead of raising the error

FALSE ON ERROR
 In JSON_EXISTS
 Return FALSE instead of raising the error
EMPTY ON ERROR
 In JSON_QUERY
 Return an empty array ([]) instead of raising the error
DEFAULT 'literal_value' ON ERROR
 Return the specified value instead of raising the error

RETURNING clause
 PRETTY
▪ Can only be used in JSON_QUERY
▪ Pretty-print the returned data
 ASCII
▪ Can only be used in JSON_VALUE, JSON_QUERY
▪ Automatically escape all non-ASCII Unicode characters
in the returned data, using standard ASCII Unicode

JSON_TABLE, JSON_QUERY
 WITHOUT WRAPPER
▪ Default, no change
▪ Raise error, if scalar/multiple values in non JSON result
 WITH WRAPPER
▪ Wrap result as a JSON ARRAY [ ]
 WITH CONDITIONAL WRAPPER
▪ Wrap result as a JSON ARRAY [ ]
▪ Don’t wrap result if scalar/multiple values in JSON result

For a single JSON object or array value, it is the same as WITHOUT WRAPPER.
JSON
Example
WITH WRAPPER WITHOUT
WRAPPER
WITH CONDITIONAL
WRAPPER
{"id": 38327}
(single object)
[{"id": 38327}] {"id": 38327} {"id": 38327}
[42, "a", true]
(single array)
[[42, "a", true]] [42, "a", true] [42, "a", true]
42 [42] Error
(scalar)
[42]
42, "a", true [42, "a", true] Error
(multiple values)
[42, "a", true]
none [] Error
(no values)
[]

JSON_TABLE
 FORMAT JSON
▪ Forces JSON_QUERY behavior
▪ Therefore can have an explicit wrapper clause
 Default
▪ Projection like JSON_VALUE

sqlldr.sh
sqlldr userid=json/json control=sqlldr.ctl log=sqlldr.log bad=sqlldr.bad
filelist.dat
./data/www.json-generator.com.01.json

sqlldr.ctl
LOAD DATA
INFILE 'filelist.dat'
truncate
INTO table JSON_DATA
FIELDS TERMINATED BY ',‘
( clob_filename filler char(120)
, clob_content LOBFILE(clob_filename) TERMINATED BY EOF
, nclob_filename filler char(120)
, nclob_content LOBFILE(nclob_filename) TERMINATED BY EOF
, bfile_filename filler char(120)
, bfile_content BFILE(CONSTANT "JSON_LOAD", bfile_filename))

create bitmap index COSTCENTER_IDX
on J_PURCHASEORDER
(JSON_VALUE (PO_DOCUMENT, '$.CostCenter'));
create unique index PO_NUMBER_IDX
on J_PURCHASEORDER
(JSON_VALUE ( PO_DOCUMENT, '$.PONumber'
returning NUMBER(10)
ERROR ON ERROR));

Path Expressions
Operators
Functions
Conditions
Error Handling
Returning results
Loading JSON data
Indexing JSON data

Oracle Database SQL
Language Reference
 JSON Functions
▪ JSON_QUERY
▪ JSON_TABLE
▪ JSON_VALUE
 JSON Conditions
▪ IS JSON
▪ JSON_EXISTS
▪ JSON_TEXTCONTAINS
Oracle XMLDB
Developers Guide
 JSON in DB 12.1.0.2
 JSON Path Expressions
▪ Syntax
 Indexing JSON
▪ Syntax
 Loading JSON
▪ A Method
JSON on xmldb.nl

Stanford - Introduction to Databases (JSON)
Eclipse JSON Editor Plugin
JSONView addon (Firefox/Chrome)
JSON Schema
Get Started With JSON
www.json-generator.com
JSON Datasets: www.data.gov

Starting with JSON Path Expressions in Oracle 12.1.0.2

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Starting with JSON Path Expressions in Oracle 12.1.0.2