Postgres 15

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create table test(created_at date);
select table_schema,table_name,column_name,data_type 
from information_schema.columns where table_name='test';

CREATE TABLE




table_schema
table_name
column_name
data_type


public
test
created_at
date



SELECT 1


DO $anonymous_routine$
<<my_label>> --use the label name to refer to things inside the block
DECLARE table_name   text;
        table_schema text:='public';
        column_name  text:='created_at';
BEGIN
  FOR table_name IN SELECT ic.table_name 
                    FROM information_schema.columns AS ic 
                    WHERE  ic.column_name  = my_label.column_name
                    AND    ic.table_schema = my_label.table_schema 
  LOOP
    EXECUTE 'ALTER TABLE ' || table_name || ' ALTER COLUMN created_at TYPE timestamp without time zone;';
  END LOOP;
END my_label $anonymous_routine$;

DO


select table_schema,table_name,column_name,data_type 
from information_schema.columns where table_name='test';


table_schema
table_name
column_name
data_type


public
test
created_at
timestamp without time zone



SELECT 1