Moving data from one column to another
I'm not quite sure if I'm thinking about this the wrong way, so if that's the case perhaps someone will point me in the right direction. If however I am just missing the concept then perhaps I can get help with that. 

So any way I'll win.. or something.

What I want to do is something like this, given a table in a database, in a single query move a specific value to another row.

To clarify take this table as an example:

    id I value
    0 I 5
    1 I 2

I want to move _value_ for _id=0_ so that the table become:

    id I value
    0 I 0
    1 I 5

(OBSERVE! the value at _id=1_ doesn't matter, it's overridden and the _id=0_ _value_ is just set to zero)

My attempt this far have been a query something along the lines of:

    UPDATE atable 
    SET item = CASE id 
    WHEN '1' THEN (SELECT value FROM atable WHERE id='1') 
    WHEN '0' THEN '0' 
    END;

However this is not valid and I can't use the _SELECT_ in that fashion. So my take #2 were:

    UPDATE atable 
    SET item=(SELECT value FROM atable WHERE id='1') 
    WHERE id='0';

Which kind of works, however I can't find a way to then set _value=0_ for _id=0_

I hope it all makes sense and aren't all just ramblings now.

Just to try to be all clear:
_I want to **move** the value from one row to another, so copy will not do I can figure that one out. AND I want to do it in one query, of course I could split it up into two queries and it would be simple_

Thank's for your time reading this.

Moving data from one column to another
===

I'm not quite sure if I'm thinking about this the wrong way, so if that's the case perhaps someone will point me in the right direction. If however I am just missing the concept then perhaps I can get help with that. 

So any way I'll win.. or something.

What I want to do is something like this, given a table in a database, in a single query move a specific value to another row.

To clarify take this table as an example:

    id I value
    0 I 5
    1 I 2

I want to move _value_ for _id=0_ so that the table become:

    id I value
    0 I 0
    1 I 5

(OBSERVE! the value at _id=1_ doesn't matter, it's overridden and the _id=0_ _value_ is just set to zero)

My attempt this far have been a query something along the lines of:

    UPDATE atable 
    SET item = CASE id 
    WHEN '1' THEN (SELECT value FROM atable WHERE id='1') 
    WHEN '0' THEN '0' 
    END;

However this is not valid and I can't use the _SELECT_ in that fashion. So my take #2 were:

    UPDATE atable 
    SET item=(SELECT value FROM atable WHERE id='1') 
    WHERE id='0';

Which kind of works, however I can't find a way to then set _value=0_ for _id=0_

I hope it all makes sense and aren't all just ramblings now.

Just to try to be all clear:
_I want to **move** the value from one row to another, so copy will not do I can figure that one out. AND I want to do it in one query, of course I could split it up into two queries and it would be simple_

Thank's for your time reading this.
