postgresql基于远程数据列创建表

Question

I want to copy a table from a remote database to my local Postgres database. I face these constraints:

• I'm not the owner of the remote database, I only have select privileges.
• The table is a result of a view .
• Therefore, pg_dump is out of the option, I believe.

I find out that I can use COPY with STDIN and STDOUT in Postgres . However, COPY works only if the table on the local database is already created (if I understand correctly).

There are about a thousand columns in the table I want to copy. Obviously, I don't want to type in all the columns and data types in CREATE TABLE . What's a good solution for this?

The COPY commands (if table is created) I use are as follows (Python Interface):

copyremote = "COPY (SELECT * FROM {}.{} {}) TO stdout".format(dbname, tbname, condi)
copylocal = "COPY {} FROM stdin".format(tbname)
command = ['psql', '-h', remotepg, '-U', username, '-p', port, '-d', database, '-c', copyremote]
p1 = subprocess.Popen(command, stdout=subprocess.PIPE)
p2 = subprocess.Popen(['psql', dbname, '-c', copylocal], stdin=p1.stdout,   stdout=subprocess.PIPE)
p1.stdout.close()
return p2.communicate()[0]

Answer 1

One way would be to export the table to a csv, rsync the csv to your local machine and import the csv back to your postgres by so,

Import and Export with a header to preserve the datatypes of the table as so.

Import CSV to table with Header for columns present in first row of csv file.

COPY <TargetTableName> FROM '/path/to/csv/SourceCSVFile.csv' DELIMITERS ',' CSV HEADER

Export a table to CSV with Headers present in the first row.

COPY <SourceTableName> TO '/path/to/csv/TargetCSVFile' DELIMITERS ',' CSV HEADER;

If you have access to the table alone on the remote postges DB: you could use the -t option to pg_dump only the particular table

pg_dump -U your_rolename -d <database_name> -t <table_name> > file.sql

Answer 2

After some research, here is the solution I'm using:

• create a foreign data wrapper
• then CREATE TABLE (LIKE your_foreign_table)
• then the COPY commands above can go through

Hopefully this can be useful for someone in similar situations.