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Copy table with separate sequences for serial columns

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While creating a column management tool I came across the need to quickly replicate tables in PostgreSQL so I would not test new tools with non-test tables. To effectively test the new column tool that I ultimately intend to use on the table parts I created this new tool to duplicate parts so I’d end up with a parts1 table. When I thought I had finally gotten all the issues ironed out I encountered the following error when the column tool deletes the table:

ERROR: cannot drop table parts because other objects depend on it
DETAIL: default for table parts1 column id depends on sequence
parts_id_seq1

I’ve spent the greater part of my day working towards this solution so in short can I simply use string functions to rename the SEQUENCE_NAME variable to disassociate the parts table from the parts table or is it a more convoluted issue than that? Here is the query:

DO $$
  DECLARE
    SEQUENCE_NAME VARCHAR;
  BEGIN
    SELECT s.relname INTO SEQUENCE_NAME
    FROM pg_class AS s JOIN pg_depend d ON d.objid = s.oid 
    INNER JOIN pg_class AS t ON d.objid = s.oid AND d.refobjid = t.oid 
    INNER JOIN pg_attribute AS a ON (d.refobjid, d.refobjsubid) = (a.attrelid, a.attnum) 
    INNER JOIN pg_namespace AS n ON n.oid = s.relnamespace 
    WHERE s.relkind = 'S' 
    AND n.nspname = 'public' 
    AND t.relname='parts';

    LOCK TABLE parts;
    CREATE TABLE parts1 (LIKE parts INCLUDING ALL);
    INSERT INTO parts1 SELECT * FROM parts;
    PERFORM setval(SEQUENCE_NAME::regclass, (SELECT max(id) FROM parts)+1);
  END;
$$ LANGUAGE plpgsql;

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