database - Postgresql : Loop thorugh each table and check for column? -

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i trying write simple sql query in pgadmin loop through each table in database , change specified column name if exists. have never coded in sql after searching through many forums have managed come with:

do begin in select table_name information_schema.tables loop    if select column_name information_schema.columns table_name = 'i.table_name'     alter table i.table_name rename column old_column_name new_column_name end if; end loop;

any great.

you can skip information_schema.tables entirely. just:

do $$ declare     rec record; begin     rec in          select table_schema, table_name, column_name         information_schema.columns          column_name = 'x'     loop         execute format('alter table %i.%i rename column %i newname;',             rec.table_schema, rec.table_name, rec.column_name);     end loop; end; $$ language plpgsql;

with appropriate substitutions 'x' , newname. or make function takes them parameters, whatever.


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