Surviving parsing XML with T-SQL Steve Simon MVP SQL Server BI http://www.infogoldusa.com

SQL Server MVP Atrion Networking Corporation (Providence RI) Involved with database design for 29 years + Presenter at numerous PASS summits. Presenter at numerous SQL Saturday events. Presented at Copenhagen Nordic Rally in March. Regular contributor on SQLShack.com

Facts of life Data is not always stored in a simple format. Often data is imported from xml documents. Murphy’s law states that the data will be at the bottom of the tree. Parsing data from the tree is CPU consuming.

Today’s challenge We need a list of reports that have been run over the past 60 days. We need the name of the report. We need the dataset and data source name. We need the fields that are displayed in the report.

Let’s get started

A practical case Conversion of warehouse reports to run off of “Service Now”. Which reports are still active? Who has used them and when? Will the tables in “Service Now” contain the necessary fields?

All of our data resides in the Report Server Database

Selecting the Schema via a CTE ;WITH XMLNAMESPACES (DEFAULT 'http://schemas.microsoft.com/sqlserver/reporting/2008/01/reportdefinition' ,'http://schemas.microsoft.com/sqlserver/reporting/reportdesigner' AS rd)

We shall be utilizing two tables dbo.Catalog dbo.ExecutionLogStorage

We execute the CTE

We convert the content field to XML

FROM (SELECT RPT.Path AS ReportPath ,RPT.name AS ReportName ,CONVERT(xml, CONVERT(varbinary(max), RPT.content)) AS contentXML FROM [SQLSaturday386Albany].dbo.[Catalog] AS RPT INNER JOIN [SQLSaturday386Albany].dbo.ExecutionLogStorage Storage ON RPT.ItemID = Storage.ReportID WHERE RPT.Type = 2 –-i.e. a Report ) AS RPT

Content XML contains the ‘result set’

XML containing the field names

Type definitions

Cross Apply to get down the different branches of the tree

Ascertaining the Dataset and Data Source Names

Fields within our reports

Data source, dataset and parameters passed

The query is also available from the report

Demo 1

Reporting

Demo 2

Take-Away

Why battle with XML Parsing and processing XML data feeds. Understanding the tree structure helps with coding. Techniques may be applied to reporting. Getting access to critical data.

Surviving parsing XML with T-SQL Steve Simon MVP SQL Server BI http://www.infogoldusa.com