Data base update

Question

Hello,
I have a internal table (t_itab) with shipref no and I want to update the database table (z1sd_05) with the statement "UPDATE z1sd_05 from table t_itab."
But in my database table z1sd_05, there are 20+ fields more like date, time, username etc., My question is when I update the shipref no to database table, is date, time, username is also going to update in the database table or not?..
If not, how to achive this functionality?..
Here, date, time, username are all system fields.
Regards,
Shreekant

Answer 1

shreekant,
Below are the syntax for Updation.Based on sysntax it will happen.Suppose if you
use first one only those fields will update in database table.If you use third syntax it will update all the fields in database table by internal table fields.
1. UPDATE dbtab SET f1 ... fn.
3. UPDATE dbtab FROM TABLE itab. or
UPDATE (dbtabname) FROM TABLE itab.
So if you want to update all  use first syntax
UPDATE z1sd_05  SET  shipref_no = itab-shiref_no
                                    date =   sy-datum
                                    time = sy-uzeit
                                    username = sy-uname.
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