如何在保留原始模式的 Postgres 中将某些表从一个模式复制到另一个模式？

Question

I want to copy only 4 tables from schema1 to schema2 within same DB in Postgres. And would like to keep the tables in schema1 as well. Any idea how to do that in pgadmin as well as from postgres console?

Answer 1

You can use create table ... like

create table schema2.the_table (like schema1.the_table including all);

Then insert the data from the source to the destination:

insert into schema2.the_table
select * 
from schema1.the_table;

Answer 2

You can use CREATE TABLE AS SELECT. This ways you do not need to insert. Table will be created with data.

CREATE TABLE schema2.the_table
AS 
SELECT * FROM schema1.the_table;

Answer 3

Simple syntax that works as of v12:

CREATE TABLE newSchema.newTable
AS TABLE oldSchema.oldTable;

Answer 4

PG dump and PG restore are usually the most efficient tools.

From the command line:

pg_dump --dbname=mydb --schema=my_schema --file=/Users/my/file.dump --format=c --username=user --host=myhost --port=5432

pg_restore --dbname=mydb --schema=my_schema --format=c --username=user --host=myhost --port=5432 /Users/my/file.dump --no-owner

Answer 5

This will loop through all tables in the old schema and recreate them with data (no constraints, indexes, etc) in the new schema.

-- Set the search path to the target schema
SET search_path = newSchema;

-- Loop over the table names and recreate the tables
DO $$
DECLARE
  table_name text;
BEGIN
  FOR table_name IN
    SELECT t.table_name
    FROM information_schema.tables t
    WHERE t.table_schema = 'public'
      AND t.table_type = 'BASE TABLE'
  LOOP
    EXECUTE 'CREATE TABLE ' || quote_ident(table_name) || ' AS TABLE oldSchema.' || quote_ident(table_name);
  END LOOP;
END $$;

This is especially useful for collapsing multiple schemas for data warehousing when you don't need all the extras attached to the tables and just want a clean copy of the intact data.