How do I alter the position of a column in a PostgreSQL database table?

Question

I\'ve tried the following, but I was unsuccessful:

ALTER TABLE person ALTER COLUMN dob POSITION 37;

Answer 1

There are some workarounds to make it possible:

1. Recreating the whole table

2. Create new columns within the current table

3. Create a view

https://tableplus.com/blog/2018/09/postgresql-is-it-possible-to-alter-column-order-position-in-a-table.html

Answer 2

I was working on re-ordering a lot of tables and didn't want to have to write the same queries over and over so I made a script to do it all for me. Essentially, it:

1. Gets the table creation SQL from pg_dump
2. Gets all available columns from the dump
3. Puts the columns in the desired order
4. Modifies the original pg_dump query to create a re-ordered table with data
5. Drops old table
6. Renames new table to match old table

It can be used by running the following simple command:

./reorder.py -n schema -d database table \
    first_col second_col ... penultimate_col ultimate_col --migrate

It prints out the sql so you can verify and test it, that was a big reason I based it on pg_dump. You can find the github repo here.

Answer 3

This post is old and probably solved but I had the same issue. I resolved it by creating a view of the original table specifying the new column order.

From here I could either use the view or create a new table from the view.

    CREATE VIEW original_tab_vw AS
    SELECT a.col1, a.col3, a.col4, a.col2
    FROM original_tab a
    WHERE a.col1 IS NOT NULL --or whatever

    SELECT * INTO new_table FROM original_tab_vw

Rename or drop the original table and set the name of the new table to the old table.