Auto-increment functionality in the MySQL database implemented in the Oracle database

In the MySQL database, you want to implement a self-increment function of the data (that is, when inserting this data, fill in null, System automatic + 1), you can use the statement auto-increment directly in the column.

int Primary Key Auto_increment

This is not used in Oracle databases. The following describes how to implement the self-increment of the ID column in an Oracle database.

1 Create a table cutomers. (Needless to say)

1 Create TableCustomers (2Id Number(Ten),  3Namevarchar( -) not NULL,4Addressvarchar( -),5Phonevarchar( -),6        constraintCustomers_id_pkPrimary Key(ID),7        constraintCustomers_name_ukUnique(name)8        9)

2 Create a sequence sequence.

1 CREATE SEQUENCE customers_sequence 2  by 1---Add 1 each time 3  with 1-----Starting from 1 4 nomaxvalue-------Not set the maximum value 5 nocycle----------always accumulate, do not cycle

3 Create a trigger so that each time the data is inserted it touches the trigger to automatically add 1 to the process.

1 CREATE TRIGGER Customersid_increase 2 before 3 INSERT  on  for Each ROW 4 begin 5 Select  into  from dual; 6 End;

4 Validation: When inserting data, the ID column can be directly written as null.

 1  insert  into  customers values  (null ,  tom   ", "  miami  , "   18376326890  ) 

2 Insert  into Values (null,'Wade','Chicago','  13157632690')

To view the data in a table, you can:

1 Tom Miami 18376326890 ...............
2 Wade Chicago ...... ..... ........................

The ID column implements the Automatic plus 1 feature.

Auto-increment functionality in the MySQL database implemented in the Oracle database