Which version are you using? The following worked for me with CF9 / MS SQL (varbinary column)
<cfquery name="getPdf" ....>
SELECT Data
FROM someTable
WHERE ID = 123
</cfquery>
<cfset pdfBinary = getPdf.data[1]>
<cfpdf action="extractText" source="pdfBinary" name="result">
<cfdump var="#result#">
: , cfpdf , queryName.columnName "". , cfpdf , .. queryName.columnName[ 1 ]. - .