322
votes

I am trying to copy an entire table from one database to another in Postgres. Any suggestions?

20
If you're okay with installing DBeaver, it has a really simple way of transferring between two databases you're connected to. Just right click the source table and select Export Data, target a Database table(s) and set the target as the destination database.rovyko

20 Answers

371
votes

Extract the table and pipe it directly to the target database:

pg_dump -t table_to_copy source_db | psql target_db

Note: If the other database already has the table set up, you should use the -a flag to import data only, else you may see weird errors like "Out of memory":

pg_dump -a -t my_table my_db | psql target_db
118
votes

You can also use the backup functionality in pgAdmin II. Just follow these steps:

  • In pgAdmin, right click the table you want to move, select "Backup"
  • Pick the directory for the output file and set Format to "plain"
  • Click the "Dump Options #1" tab, check "Only data" or "only Schema" (depending on what you are doing)
  • Under the Queries section, click "Use Column Inserts" and "User Insert Commands".
  • Click the "Backup" button. This outputs to a .backup file
  • Open this new file using notepad. You will see the insert scripts needed for the table/data. Copy and paste these into the new database sql page in pgAdmin. Run as pgScript - Query->Execute as pgScript F6

Works well and can do multiple tables at a time.

88
votes

Using dblink would be more convenient!

truncate table tableA;

insert into tableA
select *
from dblink('hostaddr=xxx.xxx.xxx.xxx dbname=mydb user=postgres',
            'select a,b from tableA')
       as t1(a text,b text);
39
votes

Using psql, on linux host that have connectivity to both servers

( export PGPASSWORD=password1 
  psql -U user1 -h host1 database1 \
  -c "copy (select field1,field2 from table1) to stdout with csv" ) \
| 
( export PGPASSWORD=password2 
  psql -U user2 -h host2 database2 \ 
   -c "copy table2 (field1, field2) from stdin csv" )
24
votes

First install dblink

Then, you would do something like:

INSERT INTO t2 select * from 
dblink('host=1.2.3.4
 user=*****
 password=******
 dbname=D1', 'select * t1') tt(
       id int,
  col_1 character varying,
  col_2 character varying,
  col_3 int,
  col_4 varchar 
);
15
votes

If you have both remote server then you can follow this:

pg_dump -U Username -h DatabaseEndPoint -a -t TableToCopy SourceDatabase | psql -h DatabaseEndPoint -p portNumber -U Username -W TargetDatabase

It will copy the mentioned table of source Database into same named table of target database, if you already have existing schema.

13
votes

Use pg_dump to dump table data, and then restore it with psql.

10
votes

You could do the following:

pg_dump -h <host ip address> -U <host db user name> -t <host table> > <host database> | psql -h localhost -d <local database> -U <local db user>

8
votes

Here is what worked for me. First dump to a file:

pg_dump -h localhost -U myuser -C -t my_table -d first_db>/tmp/table_dump

then load the dumped file:

psql -U myuser -d second_db</tmp/table_dump
8
votes

To move a table from database A to database B at your local setup, use the following command:

pg_dump -h localhost -U owner-name -p 5432 -C -t table-name database1 | psql -U owner-name -h localhost -p 5432 database2
5
votes

I tried some of the solutions here and they were really helpful. In my experience best solution is to use psql command line, but sometimes i don't feel like using psql command line. So here is another solution for pgAdminIII

create table table1 as(
 select t1.* 
 from dblink(
   'dbname=dbSource user=user1 password=passwordUser1',
   'select * from table1'  
  ) as t1(
    fieldName1 as bigserial,
    fieldName2 as text,
    fieldName3 as double precision 
  )
 )

The problem with this method is that the name of the fields and their types of the table you want to copy must be written.

5
votes

Same as answers by user5542464 and Piyush S. Wanare but split in two steps:

pg_dump -U Username -h DatabaseEndPoint -a -t TableToCopy SourceDatabase > dump
cat dump | psql -h DatabaseEndPoint -p portNumber -U Username -W TargetDatabase

otherwise the pipe asks the two passwords in the same time.

4
votes

pg_dump does not work always.

Given that you have the same table ddl in the both dbs you could hack it from stdout and stdin as follows:

 # grab the list of cols straight from bash

 psql -d "$src_db" -t -c \
 "SELECT column_name 
 FROM information_schema.columns 
 WHERE 1=1 
 AND table_name='"$table_to_copy"'"
 # ^^^ filter autogenerated cols if needed     

 psql -d "$src_db" -c  \
 "copy ( SELECT col_1 , col2 FROM table_to_copy) TO STDOUT" |\
 psql -d "$tgt_db" -c "\copy table_to_copy (col_1 , col2) FROM STDIN"
4
votes

As an alternative, you could also expose your remote tables as local tables using the foreign data wrapper extension. You can then insert into your tables by selecting from the tables in the remote database. The only downside is that it isn't very fast.

3
votes

Check this python script

python db_copy_table.py "host=192.168.1.1 port=5432 user=admin password=admin dbname=mydb" "host=localhost port=5432 user=admin password=admin dbname=mydb" alarmrules -w "WHERE id=19" -v
Source number of rows = 2
INSERT INTO alarmrules (id,login,notifybyemail,notifybysms) VALUES (19,'mister1',true,false);
INSERT INTO alarmrules (id,login,notifybyemail,notifybysms) VALUES (19,'mister2',true,false);
2
votes

You have to use DbLink to copy one table data into another table at different database. You have to install and configure DbLink extension to execute cross database query.

I have already created detailed post on this topic. Please visit this link

2
votes

If the both DBs(from & to) are password protected, in that scenario terminal won't ask for the password for both the DBs, password prompt will appear only once. So, to fix this, pass the password along with the commands.

PGPASSWORD=<password> pg_dump -h <hostIpAddress> -U <hostDbUserName> -t <hostTable> > <hostDatabase> | PGPASSWORD=<pwd> psql -h <toHostIpAddress> -d <toDatabase> -U <toDbUser>
2
votes

I was using DataGrip (By Intellij Idea). and it was very easy copying data from one table (in a different database to another).

First, make sure you are connected with both DataSources in Data Grip.

Select Source Table and press F5 or (Right-click -> Select Copy Table to.)

This will show you a list of all tables (you can also search using a table name in the popup window). Just select your target and press OK.

DataGrip will handle everything else for you.

0
votes

If you run pgAdmin (Backup: pg_dump, Restore: pg_restore) from Windows it will try to output the file by default to c:\Windows\System32 and that's why you will get Permission/Access denied error and not because the user postgres is not elevated enough. Run pgAdmin as Administrator or just choose a location for the output other than system folders of Windows.

0
votes

for DBeaver tool users, you can "Export data" to table in another database.

enter image description here

Only error I kept facing was because of wrong postgres driver.

SQL Error [34000]: ERROR: portal "c_2" does not exist
    ERROR: Invalid protocol sequence 'P' while in PortalSuspended state.

Here is a official wiki on how to export data: https://github.com/dbeaver/dbeaver/wiki/Data-transfer