--https://www.ibm.com/docs/en/integration-bus/9.0.0?topic=performance-esql-code-tips
DECLARE myChar CHAR;
DECLARE inputRef REFERENCE TO InputRoot.MRM.myParent.myRepeatingRecord[1];
WHILE LASTMOVE(inputRef) DO
    SET myChar = inputRef;
    MOVE inputRef NEXTSIBLING NAME 'myRepeatingRecord';
END WHILE;