update tableA set row = recordA  where pkColumn = value;   

the answer, as always, is - it depends.

do you tend to update very few of the columns? It might be worth while to generate an update for just the columns that have changed. That will cut down on the redo and undo generated.

do you tend to update lots of unique sets of columns (eg: you could end up generating MILLIONS of unique sql statements here). then I'd go for the single statement.

do you have an unindex foreign key pointing to these tables? I'd surely want to skip updating the primary key then (to avoid a full table lock on the child table).

(Oracle does have an optimization to skip index maintenance if you have not modified the key value - but -

ops$tkyte%ORA10GR2>
ops$tkyte%ORA10GR2> create table p ( x int primary key, y int );

Table created.

ops$tkyte%ORA10GR2> create table c ( x references p, y int );

Table created.

ops$tkyte%ORA10GR2>
ops$tkyte%ORA10GR2> insert into p values ( 1, null );

1 row created.

ops$tkyte%ORA10GR2> insert into p values ( 2, null );

1 row created.

ops$tkyte%ORA10GR2> insert into c values ( 2, null );

1 row created.

ops$tkyte%ORA10GR2> commit;

Commit complete.

ops$tkyte%ORA10GR2> update c set y = 0;

1 row updated.

ops$tkyte%ORA10GR2> declare
  2          pragma autonomous_transaction;
  3          l_rec p%rowtype;
  4  begin
  5          l_rec.x := 1;
  6          l_rec.y := 2;
  7          update p set row = l_rec where x = l_rec.x;
  8          commit;
  9  end;
 10  /
declare
*
ERROR at line 1:
ORA-00060: deadlock detected while waiting for resource
ORA-06512: at line 7

that won't do a thing for the full table lock of an unindexed foreign key - here we deadlocked ourselves over trying to lock table C, the update could not get the full table lock....



In general, I'd support updating all of the columns MINUS the primary key.


But, don't forget, the java programmers STILL HAVE TO BIND TO THE PLSQL CALL. They will have to write as much code to fix the problem - they MUST BIND to the plsql call or you will have achieved.....

nothing.