Read from insert?

Question

Is it possible to query the database from a create statement? For instance, when the create service is called, an SQL statement is executed and those results are included in the insert. If this is possible, what is the general approach?
Thanks!
Dave

Answer 1

You can write a create procedure in XQSE that first reads and then calls another create procedure. Any procedure can be designated a create procedure, but in order to be a primary create procedure, it has to adhere to the parameter and return type convention.
Here is an example that only adds an address if none exists for that customer, you can add it in the RetailDataspace to Normalized/Customer/Address.ds:
(::pragma  function <f:function kind="create" visibility="public" isPrimary="false" xmlns:f="urn:annotations.ld.bea.com"/>::)
declare procedure tns:addAddressCheckFirst($arg0 as element(ns7:ADDRESS)) as element(ns7:Address_KEY)?{
    declare $sameCustomerAddresses := tns:getAddress()[CustomerID = $arg0/CustomerID];
    fn-bea:probe($sameCustomerAddresses);
    if (not(fn:exists($sameCustomerAddresses))) then {
        return value tns:createADDRESS($arg0);
    } else {
        return value ();
};Recommended reading:
More about procedure types:
[http://download.oracle.com/docs/cd/E13162_01/odsi/docs10gr3/datasrvc/Data%20Service%20Types%20and%20Functions.html]
[http://download.oracle.com/docs/cd/E13162_01/odsi/docs10gr3/xquery/xqse.html]
[http://download.oracle.com/docs/cd/E13162_01/odsi/docs10gr3/odsi10gr3/How%20To%20Develop%20Good%20XQSEs.html]