Putting restrictions on pg_dump?

On Wed, 4 Jan 2006 21:00:25 -0800, Benjamin Smith <lists@benjamindsmith.com> wrote:

Is there a way to put a limit on pg_dump, so that it doesn't dump ALL data,
but that matching a particular query?

Something like:

pg_dump -da --attribute-inserts -t "customers" \
--matching-query="select * from customers where id=11";

I'd like to selectively dump information from a query, but using the output
format from pg_dump so that it can be used to create a (partial) database.

Can this sort of thing be done?

Not directly with pg_dump.

You could create a table (create table customers_1 as select * from
customers where id=11) and dump that but remember to change the
tablename in the dump file or after loading it. You dont get any
pk/fk/indexes on the table definition.

You could also use copy to stdout/stdin.

eg dump
psql -d dbname -c "create temp table dump as select * from customers
where id=11; copy dump to stdout;" >dumpfile

eg restore
psql -d newdb -c "copy customers from stdin" <dumpfile

You might need to play around with supplying username/password.

klint.

+---------------------------------------+-----------------+
: Klint Gore                            : "Non rhyming    :
: EMail   : kg@kgb.une.edu.au           :  slang - the    :
: Snail   : A.B.R.I.                    :  possibilities  :
: Mail      University of New England   :  are useless"   :
:           Armidale NSW 2351 Australia :     L.J.J.      :
: Fax     : +61 2 6772 5376             :                 :
+---------------------------------------+-----------------+

Good ideas, all. but, what about keeping things like check constraints,
foreign keys, etc?

Hmmm... maybe, if I dumped the entire DB schema, with no data, and then looped
thru the tables, creating a temp table (as you describe) with a funky name
(such as TABLEaBcDeFgH_U) and then pg_dumping that, and then using a regex to
rename the table in the output... (eg

/TABLE\s+TABLEaBcDeFgH_U/TABLE customers/

Ugh. I was hoping there was a cleaner way...

-Ben

On Wednesday 04 January 2006 23:35, you wrote:

On Wed, 4 Jan 2006 21:00:25 -0800, Benjamin Smith <lists@benjamindsmith.com>

wrote:

Is there a way to put a limit on pg_dump, so that it doesn't dump ALL

data,

but that matching a particular query?

Something like:

pg_dump -da --attribute-inserts -t "customers" \
--matching-query="select * from customers where id=11";

I'd like to selectively dump information from a query, but using the

output

format from pg_dump so that it can be used to create a (partial) database.

Can this sort of thing be done?

Not directly with pg_dump.

You could create a table (create table customers_1 as select * from
customers where id=11) and dump that but remember to change the
tablename in the dump file or after loading it. You dont get any
pk/fk/indexes on the table definition.

You could also use copy to stdout/stdin.

eg dump
psql -d dbname -c "create temp table dump as select * from customers
where id=11; copy dump to stdout;" >dumpfile

eg restore
psql -d newdb -c "copy customers from stdin" <dumpfile

You might need to play around with supplying username/password.

klint.

+---------------------------------------+-----------------+
: Klint Gore                            : "Non rhyming    :
: EMail   : kg@kgb.une.edu.au           :  slang - the    :
: Snail   : A.B.R.I.                    :  possibilities  :
: Mail      University of New England   :  are useless"   :
:           Armidale NSW 2351 Australia :     L.J.J.      :
: Fax     : +61 2 6772 5376             :                 :
+---------------------------------------+-----------------+

--
"The best way to predict the future is to invent it."
- XEROX PARC slogan, circa 1978

On Thu, 5 Jan 2006 09:59:45 -0800, Benjamin Smith <lists@benjamindsmith.com> wrote:

Good ideas, all. but, what about keeping things like check constraints,
foreign keys, etc?

how about something like
pg_dump -s -t customers dbname >customers.def

Hmmm... maybe, if I dumped the entire DB schema, with no data, and then looped
thru the tables, creating a temp table (as you describe) with a funky name
(such as TABLEaBcDeFgH_U) and then pg_dumping that, and then using a regex to
rename the table in the output... (eg

/TABLE\s+TABLEaBcDeFgH_U/TABLE customers/

Ugh. I was hoping there was a cleaner way...

Make a script with all the commands in it. You should be able to
manually make a file that is similar to what pg_dump does.

pg_dump -s -t customers dbname >customers.def
echo "copy customers from stdin;" >>customers.def
psql -d dname -c "create temp table dump as select * from customers
where id=11; copy dump to stdout;" >>customers.def
echo "\." >>customers.def

klint.

+---------------------------------------+-----------------+
: Klint Gore                            : "Non rhyming    :
: EMail   : kg@kgb.une.edu.au           :  slang - the    :
: Snail   : A.B.R.I.                    :  possibilities  :
: Mail      University of New England   :  are useless"   :
:           Armidale NSW 2351 Australia :     L.J.J.      :
: Fax     : +61 2 6772 5376             :                 :
+---------------------------------------+-----------------+