Re: [COMMITTERS] pgsql: Improve the manual's discussion of partitioning.

tgl(at)postgresql(dot)org (Tom Lane) wrote:

> Log Message:
> -----------
> Improve the manual's discussion of partitioning. Recommend using a
> trigger instead of a rule to redirect insertions, use NEW.* notation
> where appropriate, some other updates and adjustments. David Fetter
> and Tom Lane

I have a fix (1) and two comments (2 and 3) in the documentation.

1. "IF (logdate)" should be "IF (NEW.logdate)" in the trigger function.
INSERT fails without "NEW." before logdate.
=# INSERT INTO measurement VALUES(1, DATE '2007-12-03', 0, 0);
ERROR: column "logdate" does not exist

2. What is the purpose of "2. Next we create one partition ..." ?
We will recreate tables in "3. We must add non-overlapping table
constraints...". Is the chapter 2 useless? When users copy-and-paste
the codes in the topic, they run into errors at the chapter 3.

3. Is it worth reversing the order of checking date in the trigger function?
I think the newer partions are more often inserted in this case.
If we check the newer partion first, we can skip the remaining checks.
This is one of the advantage of by-trigger partitioning than by-rule.

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center