In a Bank’* database, there are two tables ‘Customer’ and ‘Transaction’ as shown below.
Customer
| Acc_No | Cust_Name | Cust_City | Cust_Phone | Open_Bal |
| 2101001 | Sunita | Ambala | 9710557614 | 10000 |
| 2201002 | Sandhya | Patna | 8223545233 | 15000 |
| 2301003 | Vivek | New Delhi | 9972136576 | 13000 |
| 2401004 | Meena | New Delhi | 9321305453 | 10000 |
Transaction
| Trans_Id | Acc_No | Transaction_Type | Amount |
| Tr001 | 2301003 | Credit | 15000 |
| Tr002 | 2201002 | Credit | 20000 |
| Tr003 | 2101001 | Debit | 3500 |
| Tr004 | 2301003 | Credit | 26000 |
| Tr005 | 2301003 | Credit | 24000 |
Consider these tables while attempting the questions given below:
(i) Identify the candidate keys of Customer table.
(ii) Briefly explain the concept of Candidate keys.
(iii) Which column can be considered as foreign key column in Transaction table?
(iv) Identify Primary Key column of Transaction table.
