Update multiple row in SQL

[Iceberg]

Hi All can anyone help with the below scenario that i need to update...

FileA
Field1	Field2	Field3
A	B	I
A	B	*Blank
A	B	*Blank
C	D	O
C	D	*Blanks
C	D	*Blanks
C	D	*Blanks
C	D	*Blanks

So I need to update all A /B with value I which are *blank and C/D with O which are *blank

Thanks

[paolinosal]

Hi Iceberg,

I don't know if I understand your question, do you need something like this?

Update Ppp
Set Field3 =
Case
When Field1 = 'A'
And Field2 = 'B'
And Field3 = ' ' Then 'I'
When Field1 = 'C'
And Field2 = 'D'
And Field3 = ' ' Then 'O'
Else Field3
End;

[Scott Klement]

Paolinosal's example sounds right -- except that it updates every single row in the table, which may not be optimal.

To fix that, you could just add a 'where' cause to it, for example (reformatted a bit):

Update Ppp
Set Field3 = Case
             When Field1 = 'A' And Field2 = 'B' And Field3 = ' ' Then 'I'
             When Field1 = 'C' And Field2 = 'D' And Field3 = ' ' Then 'O'
             Else Field3
             End
where (Field1='A' and Field2='B' and Field3=' ')
   or (Field1='C' and Field2='D' and Field3=' ');