Develop X++ Code MB-500 Practice Questions (Page 5)

Questions 21–25

1. 21expert · hard

   A developer is optimizing a report that processes a large dataset. The report currently uses a while select loop to aggregate data. The developer wants to improve performance. Which change is most likely to help?

   • AUse a 'select' statement with 'group by' to perform aggregation in the database.
   • BUse a 'while select' with 'firstonly' to reduce the number of records.
   • CUse a 'for' loop with a counter and a 'select' statement inside the loop.
   • DUse a container to store all records and then process them.
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2. 22application · medium

   A developer is reviewing X++ code and encounters a best practice warning about using 'strFmt' inside a loop. The code builds a message string by concatenating fields. What is the recommended action?

   • AUse a container to store the strings and then join them at the end.
   • BMove the strFmt call outside the loop if the message is the same for all iterations, or use a StringBuilder for accumulating strings.
   • CIgnore the warning because it is only a performance suggestion and does not affect functionality.
   • DReplace strFmt with the + operator for string concatenation.
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4. 23foundation · easy

   Which X++ statement is used to insert a new record into a table?

   • Adelete()
   • Binsert()
   • Cupdate()
   • Dselect
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5. 24expert · hard

   A developer needs to insert a large number of records into a table. The records are coming from an external system and are stored in a temporary table. The developer wants to minimize the number of database round trips and avoid triggering business logic. Which approach should the developer use?

   • AUse insert_recordset to copy the records from the temporary table to the destination table.
   • BUse RecordInsertList to buffer the inserts and call insert() on each record.
   • CUse the doInsert method on each record in a loop.
   • DUse a while select loop to insert each record individually.
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6. 25application · medium

   A developer is reviewing X++ code and finds a method that uses a while select loop to sum the amounts of all sales order lines. The developer wants to resolve a best practice warning about performance. Which change should the developer make?

   • AAdd a where clause to the while select to filter records.
   • BUse the doWhile loop instead of while select.
   • CUse the sum aggregate function in a select statement.
   • DUse a for loop instead of a while loop.
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