DB2 10.5 for Linux, UNIX, and Windows

PARAMETER scalar function

The PARAMETER function represents a position in an SQL statement where the value is provided dynamically by XQuery as part of the invocation of the db2-fn:sqlquery function.


>>-PARAMETER--(--integer-constant--)---------------------------><

The schema is SYSIBM.

integer-constant: An integer constant that specifies a position index of a value in the arguments of db2-fn:sqlquery. The value must be between 1 and the total number of the arguments specified in the db2-fn:sqlquery SQL statement (SQLSTATE 42815).

The PARAMETER function represents a position in an SQL statement where the value is provided dynamically by XQuery as part of the invocation of the db2-fn:sqlquery function. The argument of the PARAMETER function determines which value is substituted for the PARAMETER function when the db2-fn:sqlquery function is executed. The value supplied by the PARAMETER function can be referenced multiple times within the same SQL statement.

This function can only be used in a fullselect contained in the string literal argument of the db2-fn:sqlquery function in an XQuery expression (SQLSTATE 42887).

Example

In the following example, the db2-fn:sqlquery function call uses one PARAMETER function call and the XQuery expression $po/@OrderDate, the order date attribute. The PARAMETER function call returns the value of order date attribute:

   xquery 
   declare default element namespace "http://posample.org"; 
   for $po in db2-fn:xmlcolumn('PURCHASEORDER.PORDER')/PurchaseOrder,
     $item in $po/item/partid 
   for $p in db2-fn:sqlquery( 
     "select description from product where promostart < PARAMETER(1)",
       $po/@OrderDate )
   where $p//@pid = $item 
   return 
   <RESULT>
     <PoNum>{data($po/@PoNum)}</PoNum>
     <PartID>{data($item)} </PartID>
     <PoDate>{data($po/@OrderDate)}</PoDate>
   </RESULT>

The example returns the purchase ID, part ID, and the purchase date for all the parts sold after the promotional start date.