Example of a Query Plan

The example query plan shown in Figure 331 provides information about how DataDirect XQuery translates the following query, which accesses one relational data source, into a SQL Select statement and how XML results are constructed.

declare option ddtek:plan-explain 'format=xhtml';
               
<myHoldings> {
               
for $holdings in collection("pubs.dbo.holdings")/holdings
               
where $holdings/userid = "Minollo"
               
return <holding
               
quantity="{$holdings/shares}">{$holdings/stockticker/text()}</holding>
               
}
               
</myHoldings>
               

            

In the following query plan, notice how the Relational Data Source node includes details about the SQL Select statement, as well as information about how the result ( $PT) is constructed.

Figure 331. Example of a Query Plan Displayed in the XQuery Editor

 
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