src/Data/Tools/BizRecord.php
final public function getKeyFields()
    {
        $keyFields = array();
        foreach ($this->keyFieldColumnMap as $fieldName => $colName) {
            $keyFields[$fieldName] = $this->varValue[$fieldName];
        }
        return $keyFields;
    }
final public function getKeyFields()
    {
        $keyFields = array();
        foreach ($this->keyFieldColumnMap as $fieldName => $colName) {
            $keyFields[$fieldName] = $this->varValue[$fieldName];
        }
        return $keyFields;
    }
Get a list of fields (name) who are defined as keys columns

@return array array of key fields