Talking about transactions (db transactions),
does a read operation have always precede a write operation?
That's obvious, isn't it?
Thanks in advance
*Of course my question doesn't take into account any specific locking protocol or whatever it's actually related to the following question:
A transaction T is defined by a partial order, termed <, such that: if r[x] and w[x] belong to T, then r[x] < w[x].