(a) Write an Oracle-compatible SQL command that creates a function the returns the vendor_id for a particular invoice_id provided as input to the function. (b) Write a SELECT command that uses the function.

EEE INVOICES Columns Data Constraints Grants Statistics Triggers Flashback Dependencies Details Partitions Indexes SQL ??? ? Actions.. . NULLABLE DATA DEFAULT | COLUMN-ID $ COMMENTS DATA TYPE NUMBER NUMBER COLUMN NAME 1 INVOICE ID 2 VENDOR_ID 3 INVOICE_NUMBER VARCHAR2(50 BYTE) No 4 INVOICE DATE 5 INVOICE TOTALNUMBER(9,2) 6 PAYMENT TOTAL NUMBER(9,2) 7 CREDIT_TOTAL NUMBER(9,2) 8 TERMS_ID 9 INVOICE DUE DATE DATE 10 PAYMENT DATE DATE 1 (null) 2 (null) 3 (null) 4 (null) 5 (null) 6 (nul) 7 (null) 8 (null) 9 (null) 10 (null) (null) (null) (null) (null) (null) No 0 DATE No 0 Yes No 0 (null) (null) Yes (null) NUMBER EEE INVOICES Columns Data Constraints Grants Statistics Triggers Flashback Dependencies Details Partitions Indexes SQL ??? ? Actions.. . NULLABLE DATA DEFAULT | COLUMN-ID $ COMMENTS DATA TYPE NUMBER NUMBER COLUMN NAME 1 INVOICE ID 2 VENDOR_ID 3 INVOICE_NUMBER VARCHAR2(50 BYTE) No 4 INVOICE DATE 5 INVOICE TOTALNUMBER(9,2) 6 PAYMENT TOTAL NUMBER(9,2) 7 CREDIT_TOTAL NUMBER(9,2) 8 TERMS_ID 9 INVOICE DUE DATE DATE 10 PAYMENT DATE DATE 1 (null) 2 (null) 3 (null) 4 (null) 5 (null) 6 (nul) 7 (null) 8 (null) 9 (null) 10 (null) (null) (null) (null) (null) (null) No 0 DATE No 0 Yes No 0 (null) (null) Yes (null) NUMBER