Re: please define 'statement' in the glossary

"David G. Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com> writes:
> Ok. That explains why "statement_timestamp() and transaction_timestamp()
> return the same value during the first command of a transaction," isn't
> just stating the obvious. transaction_timestamp() literally returns the
> value statement_timestamp().

Right. I'm tempted to be more explicit about that, along the lines of

<function>statement_timestamp()</function> and <function>transaction_timestamp()</function>
- return the same value during the first statement of a transaction, but might
- differ during subsequent statements.
+ return the same value during the first statement of a transaction,
+ because the transaction timestamp is set by copying the statement
+ timestamp when a new transaction starts.

I didn't include that change below though; perhaps it has too much
whiff of implementation detail.

> I'm fine with this entire section assuming/stating that extended protocol
> is in effect and that 53.2.2.1 explains how these behave when executing a
> multi-statement simple protocol "script".

It's incorrect to claim that this only applies to extended protocol,
and besides I thought you didn't want to mention protocol details
here. I can't argue with documenting it in the protocol chapter
though. So about like this?

regards, tom lane