更新Oracle 11g数据库中用户的最新行？

Question

My code is in this sqlFiddle .

Creating the table

create table my_table ( pk number, created date, user_name varchar2(200), start_date date);

insert into my_table (pk, created,user_name) values (1, sysdate-1, 'bob');
insert into my_table (pk, created,user_name) values (2, sysdate-2, 'frank');
insert into my_table (pk, created,user_name) values (3, sysdate,'bob');
insert into my_table (pk, created,user_name) values (4, sysdate,'frank');

Updating:

update my_table
set start_date = sysdate
  from my_table
 where pk = ( select max(pk) from my_table where user_name = 'bob' );

SQLFiddle gives me this error:

ORA-00933: SQL command not properly ended : update my_table set start_date = sysdate from my_table where pk = ( select max(pk) from my_table where user_name = 'bob' )

But I'm sure I have a semicolon in there in the right place.

What gives? I'm quite new to SQL, and thought this would work.

Answer 1

You don't need the from :

update my_table
    set start_date = sysdate
     where pk = ( select max(pk) from my_table where user_name = 'bob' );

Answer 2

Remove the from clause, you already have it at the top:

update my_table
set start_date = sysdate
 where pk = ( select max(pk) from my_table where user_name = 'bob' );