This is a reply to the SET column UPDATE question (I deleted to e-mail, oups!).
The question was that you have a column of type SET and value ("a,b,c") and you want
to make this ("a,b,c,d")
In the __MySQL MANUAL__ it says that the SET type is actually stored numerically and
in particular "with the low-order bit of the stored value corresponding to the first
set member" and a couple of lines further down "If a number is stored into a SET
column, the bits that are set in the binary representation of the number determine the
set members in the column value"
i.e. if your set has values "a,b,c,d" then:
a = 0001
b = 0010
c = 0100
d = 1000
So if you do an update of the form:
UPDATE table SET set_var=3 WHERE my_cond;
it would actually make set_var=("a,b") for the tuple that my_cond holds since the
ten_Base 3 is the binary 11.
So in your case that you want to add "d" to a tuple that is "a,b,c" you do
UPDATE table SET set_val=15 WHERE my_cond;
since 15 is 1111 in binary (the leftmost '1' is the flag that tells mysql to add the
"d" in your set)
does it make any sense?
regards,
thalis
-------------------------------+
You're definitely on their list.
The correct question to ask is what list it is.
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