Oracle Query：如何在插入记录时创建唯一键？

Question

Here I have few records.

Id is primary key and auto increment.

Name is Varchar2

Result is Char

Registration Number is unique key and it is combination of Name-Id. How can I make my registration number insert in default like this?

My table looks like:

id.  Name.   Result.   Registration Number
___________________________________________

1.   John     P.        John-1
2.   Tom.     P.        Tom-2
3.   John.    P.        John-3
4.   Jerry.   F.        Jerry-4

Answer 1

try this

CREATE TABLE t1
(
  id  NUMBER  NOT NULL,
  FirstName VARCHAR2(20),
  LastName VARCHAR2(20),
  FullName VARCHAR2(100) GENERATED ALWAYS AS (FirstName || ' ' || LastName || '' || id) VIRTUAL,
  PRIMARY KEY (id)
);