Hi Subramanian,

Good morning and thanks for approaching us for clarifying the doubts. Please read through the lines from Oracle Implementation Guide regarding secondary ledger and impact of using Journal as conversion level- especially those underlined and consider it for your requirements.

A secondary ledger is an optional ledger linked to a primary ledger for the purpose of tracking alternative accounting. A secondary ledger can differ from its primary ledger by using a different accounting method, chart of accounts, accounting calendar, currency, or processing options. All or some of the journal entries processed in the primary ledger are transferred to the secondary ledger, based on your configuration options. The transfers are completed based on the conversion level selected.
There are four conversion levels:
• Balance: Only Oracle Fusion General Ledger balances are transferred to the secondary ledger.
• Journal: General Ledger journal posting process transfers the journal entries to the secondary ledger.
• Subledger: Oracle Fusion Subledger Accounting creates subledger journals to subledger level secondary ledgers
as well as reporting currencies.
• Adjustments Only: Incomplete accounting representation that only holds adjustments. The adjustments can be
manual or detailed adjustments from Subledger Accounting. This type of ledger must share the same chart of
accounts, accounting calendar, and period type combination, and currency as the associated primary ledger.

Secondary ledgers provide functional benefits, but produce large volumes of additional journal entry and balance data, resulting in additional performance and memory costs. When adding a secondary ledger, consider your needs for secondary ledgers or reporting currencies, and select the least costly data conversion level that meets your requirements. The journal and subledger data conversion levels are much more expensive, requiring duplication of most general ledger and subledger journal entries, as well as general ledger balances.

Do not use journal or subledger level reporting currencies if your organization has only an infrequent need to translate your financial statements to your parent company's currency for consolidation purposes. Standard translation functionality meets this need. Consider using journal or subledger level reporting currencies when any of the following conditions exist.
• You operate in a country whose unstable currency makes it unsuitable for managing your business. As a consequence, you need to manage your business in a more stable currency while retaining the ability to report in
the unstable local currency.
• You operate in a country that is part of the European Economic and Monetary Union (EMU), and you choose to account and report in both the European Union currency and your National Currency Unit (NCU)

If you still want to go ahead with using Journal as conversion level. prepare an excel with comparison of attributes which you want to use in primary and secondary ledgers and then proceed to create it logically considering the data security and business transaction in mind.

Thanks & Regards
Kirshna Roshan