I'm looking into using a company that uses Yodlee's data aggregation service and have looked some sample output that includes account information and transactions. I noticed that the unique ID and account number for the account are not housed in the table containing transactions. How do people typically go about mapping transactions to a particular count when placing multiple accounts into a relational database? It seems to me that there is no field to link the table containing account information and transaction information together.
You can use the identifier called "itemAccountId" which is a Yodlee internal id tied to uniquely identify an account. This identifier is present for an account as well as each transactions. Using this id you can segregate the transactions under same account.
Please go through the sample responses of these two APIs getItemSummaryForItem1 and executeUserSearchRequest