Hello All,
I am new to XML so bear with me. I have a situation where I need to extract column field name from XML file stored in table column. I am trying to use extract function but getting NULL value from below SQL. In this case I am expecting to have list of all caption text listed. Please let me know what wrong I am doing below.

SELECT X.XML.EXTRACT('/report/criteria/columns/column/columnHeading/caption/text()').GETSTRINGVAL() FROM <Table_name>


- <saw:report xmlns:saw="com.siebel.analytics.web/report/v1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlVersion="201008230" xmlns:sawx="com.siebel.analytics.web/expression/v1.1">
- <saw:criteria xsi:type="saw:simpleCriteria" subjectArea=""Study Execution"" withinHierarchy="true">
- <saw:columns>
- <saw:column xsi:type="saw:regularColumn" columnID="cf5c435bd3d235724">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"Study"."Sponsor Name"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cf48a34febca748ff">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"Study"."Project Status"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="ce51ccb4c38ed538f">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"Project Goverance"."Project Manager"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cf4bc5bea2531f3fe">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"Study"."Indication"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="c430e05de61704a98">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Key Deviations"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cf658139b454c5a7f">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Non-Key Deviations"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="c1276c4cb2684ce42">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Key/Non-Key NA Deviations"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cea25118bedcf2772">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Site Life Cycle Metrics"."# of Sites Activated by Deviation"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
<saw:formatSpec suppress="repeat" wrapText="true" />
</saw:displayFormat>
- <saw:tableHeading>
- <saw:caption fmt="text">
<saw:text>Site Life Cycle Metrics</saw:text>
</saw:caption>
</saw:tableHeading>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
- <saw:caption fmt="text">
<saw:text># of Sites Activated</saw:text>
</saw:caption>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cae9b8f9cb7b8daba">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Key Deviations per Active Site"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
- <saw:formatSpec suppress="repeat" wrapText="true">
<saw:dataFormat minDigits="2" maxDigits="2" commas="true" negativeType="minus" xsi:type="saw:number" />
</saw:formatSpec>
</saw:displayFormat>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cbb0790d62c120f67">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Site Life Cycle Metrics"."# of Sites Activated with FPS by Deviation"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
<saw:formatSpec suppress="repeat" wrapText="true" />
</saw:displayFormat>
- <saw:tableHeading>
- <saw:caption fmt="text">
<saw:text>Site Life Cycle Metrics</saw:text>
</saw:caption>
</saw:tableHeading>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
- <saw:caption fmt="text">
<saw:text># of Recruiting Sites (FPS)</saw:text>
</saw:caption>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cec29c1b67bd731bc">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Key Deviations per Recruiting Site (FPS)"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
- <saw:formatSpec suppress="repeat" wrapText="true">
<saw:dataFormat minDigits="2" maxDigits="2" commas="true" negativeType="minus" xsi:type="saw:number" />
</saw:formatSpec>
</saw:displayFormat>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cf52f2d88d2e78ff9">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Subject Life Cycle Metrics"."# of Actual Subjects Randomized by Deviation"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
<saw:formatSpec suppress="repeat" wrapText="true" />
</saw:displayFormat>
- <saw:tableHeading>
- <saw:caption fmt="text">
<saw:text>Subject Life Cycle Metrics</saw:text>
</saw:caption>
</saw:tableHeading>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
- <saw:caption fmt="text">
<saw:text># of Actual Subjects Randomized</saw:text>
</saw:caption>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="c804cdbe82e3fa7f3">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Key Deviations per Rand Patient"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
- <saw:formatSpec suppress="repeat" wrapText="true">
<saw:dataFormat minDigits="2" maxDigits="2" commas="true" negativeType="minus" xsi:type="saw:number" />
</saw:formatSpec>
</saw:displayFormat>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="ce344decda5f6fd83">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Total Waivers"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
<saw:formatSpec suppress="repeat" wrapText="true" />
</saw:displayFormat>
- <saw:tableHeading>
- <saw:caption fmt="text">
<saw:text>Deviation Metrics</saw:text>
</saw:caption>
</saw:tableHeading>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec />
</saw:displayFormat>
- <saw:caption fmt="text">
<saw:text># Total Waivers</saw:text>
</saw:caption>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="c0d6921698af79211">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Inclusion/Exclusion Waivers"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cef66aab5dfc4449d">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"- Deviation Metrics"."# Other Waivers"</sawx:expr>
</saw:columnFormula>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="cb963b668b55786bb">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"Deviation Level"."Deviation Level"</sawx:expr>
</saw:columnFormula>
- <saw:displayFormat>
- <saw:formatSpec suppress="repeat" wrapText="true" interaction="clientEvent">
<saw:clientEventSpec channel="Level" />
</saw:formatSpec>
</saw:displayFormat>
- <saw:columnHeading>
- <saw:displayFormat>
<saw:formatSpec interaction="none" />
</saw:displayFormat>
</saw:columnHeading>
</saw:column>
- <saw:column xsi:type="saw:regularColumn" columnID="c15b89d8487d41b29">
- <saw:columnFormula>
<sawx:expr xsi:type="sawx:sqlExpression">"Deviation"."Deviation Type"</sawx:expr>
</saw:columnFormula>
</saw:column>
</saw:columns>
</saw:criteria>
</saw:report>