Completely copying a postgres table with SQL

Question

DISCLAIMER: This question is similar to the stack overflow question here, but none of those answers work for my problem, as I will explain later.

I'm trying to copy a large table (~40M rows, 100+ columns) in postgres where a lot of the columns are indexed. Currently I use this bit of SQL:

CREATE TABLE <tablename>_copy (LIKE <tablename> INCLUDING ALL);
INSERT INTO <tablename>_copy SELECT * FROM <tablename>;

This method has two issues:

1. It adds the indices before data ingest, so it will take much longer than creating the table without indices and then indexing after copying all of the data.
2. This doesn't copy `SERIAL' style columns properly. Instead of setting up a new 'counter' on the the new table, it sets the default value of the column in the new table to the counter of the past table, meaning it won't increment as rows are added.

The table size makes indexing a real time issue. It also makes it infeasible to dump to a file to then re-ingest. I also don't have the advantage of a command line. I need to do this in SQL.

What I'd like to do is either straight make an exact copy with some miracle command, or if that's not possible, to copy the table with all contraints but without indices, and make sure they're the constraints 'in spirit' (aka a new counter for a SERIAL column). Then copy all of the data with a SELECT * and then copy over all of the indices.

Sources

1. Stack Overflow question about database copying: This isn't what I'm asking for for three reasons

   • It uses the command line option pg_dump -t x2 | sed 's/x2/x3/g' | psql and in this setting I don't have access to the command line
   • It creates the indices pre data ingest, which is slow
   • It doesn't update the serial columns correctly as evidence by default nextval('x1_id_seq'::regclass)

2. Method to reset the sequence value for a postgres table: This is great, but unfortunately it is very manual.

Answer 1

The create table as feature in PostgreSQL may now be the answer the OP was looking for.

https://www.postgresql.org/docs/9.5/static/sql-createtableas.html

create table my_table_copy as
  select * from my_table

This will create an identical table with the data.

Adding with no data will copy the schema without the data.

create table my_table_copy as
  select * from my_table
with no data

This will create the table with all the data, but without indexes and triggers etc.

---

create table my_table_copy (like my_table including all)

The create table like syntax will include all triggers, indexes, constraints, etc. But not include data.