Badly Needed Enquiry in Payables

[iliasachhab1]

I requested earlier also to explain me . But no guru came forward !
Is this forum for functional discussion mainly ?

I could not find much explanation in manuals etc .So, asking any knowledgable person if can help me !

what is "external_bank_account_id" in AP_payment_schedules ?
Is this "external_bank_account_id" related to "bank_account_id" in ap_bank_accounts_all ?
Also, is this "external_bank_account_id" related to "external_bank_account_id" in ap_bank_Account_uses_v ?