Re: Proposal for XML Schema Validation - Mailing list pgsql-hackers

Objective: To Add XML Schema validation and xmlvalidate functions (SQL:2008)

Description:
We’ve gone through current support of xml in postgreSQL and found that there is a check for well-formedness of xml
documentwhile inserting and updating. We want to extend this feature by adding xml schema validation. We will be
providinguser with DDL commands for creating and deleting XML Schema, also provision of associating xml schema with
tablewhile creation of new table or while altering table structure, we are planning to use libxml2 library. Proposed
syntaxis given below. 

1. End user perspective:

1.1 DDL
1.1.1    Register xmlschema          Syntax             REGSITER_XML_SCHEMA( “<URL OF SCHEMA>”, “<NAMESPACE>” ,
“<CONTENTOF SCHEMA .XSD FILE>")          We will save this information into system catalog 

1.1.2    Delete xmlschema             Syntax               DELETE_XML_SCHEMA(  “<URL OF SCHEMA>”)

1.1.3    Modification in Create Table commands    Syntax           Create table <tablename> (<col_name>
<datatype>,<col_name>      xml USE_SCHEMA <URL OF SCHEMA> )       We will keep a flag in catalog for xml schema
validationfor each table. If xml schema is specified then while every insert/update sql query we will call
valdate_xml_schema()[currently built in xml_is_well_formed() is called while inserting/updating, we can place our
functioncall just next to it] 


1.1.4    Similarly for Alter Table commands


2. Developer perspective

2.1. C-Function for Validation of xml doc

2.1.1 Validating XML
Syntax        Int<err_code>  validate_xml_schema(char xml[], char xml_schema[])This function will return 0 if validate
successfullyelse return respective error code (which we will define later)We are planning to use libxml2This function
willcalled while insert/update sql query 


________________________________________
From: Andrew Dunstan <andrew@dunslane.net>
Sent: Thursday, August 08, 2013 6:54 PM
To: Kodamasimham Pridhvi (MT2012066)
Cc: pgsql-hackers@postgresql.org; Bisen Vikrantsingh Mohansingh MT2012036; rc@iiitb.ac.in
Subject: Re: [HACKERS] Proposal for XML Schema Validation

On 08/08/2013 12:42 AM, Kodamasimham Pridhvi (MT2012066) wrote:
> Hello pgsql-hackers  ,
>     With reference to "Add XML Schema validation and xmlvalidate
> functions (SQL:2008)" in ToDo list, we have gone through pgsql-mailing
> list  but we didn't find any significant work in this area, so we are
> proposing our own model for xml schema validation . please kindly go
> through it and let us know how can we improve it.Please find the
> attached proposal document.
>
>
>
>


Please post your proposal as text, not as a PDF attachment. That's what
is preferred on this mailing list.

cheers

andrew