Re: pg_dump multi VALUES INSERT

On Sat, 19 Jan 2019 at 01:01, Surafel Temesgen <surafel3000(at)gmail(dot)com> wrote:
> if you specified --inserts option you already specified the number of rows per statement which is 1 .
> if more than one rows per statement needed it must be specified using --rows-per-insert
> and specifying one row per statement using --inserts option at the same time specify
> different number of rows per statement with --rows-per-insert option seems conflicting to me.

So you're saying an INSERT, where you insert multiple rows in a single
statement is not an insert? That logic surprises me. --inserts makes
pg_dump use INSERTs rather than COPY. --rows-per-inserts still uses
INSERTs. I'd love to know why you think there's some conflict with
that.

By your logic, you could say --column-inserts and --inserts should
also conflict, but they don't. --column-inserts happens to be coded to
imply --inserts. I really suggest we follow the lead from that. Doing
it this way reduces the complexity of the code where we build the
INSERT statement. Remember that a patch that is overly complex has
much less chance of making it. I'd really suggest you keep this as
simple as possible.

It also seems perfectly logical to me to default --rows-per-insert to
1 so that when --inserts is specified we do 1 row per INSERT. If the
user changes that value to something higher then nothing special needs
to happen as the function building the INSERT statement will always be
paying attention to whatever the --rows-per-insert value is set to.
That simplifies the logic meaning you don't need to check if --inserts
was specified.

--
David Rowley http://www.2ndQuadrant.com/
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