Module: DataMigrations::Setup

Defined in:
lib/data_migrations/setup.rb

Instance Method Summary collapse

Instance Method Details

#install_upsert ⇒ Object 



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# File 'lib/data_migrations/setup.rb', line 10

def install_upsert
  ActiveRecord::Base.connection.execute <<-sql
    CREATE FUNCTION upsert (sql_update TEXT, sql_insert TEXT)
        RETURNS VOID
        LANGUAGE plpgsql
    AS $$
    BEGIN
        LOOP
            -- first try to update
            EXECUTE sql_update;
            -- check if the row is found
            IF FOUND THEN
                RETURN;
            END IF;
            -- not found so insert the row
            BEGIN
                EXECUTE sql_insert;
                RETURN;
                EXCEPTION WHEN unique_violation THEN
                    -- do nothing and loop
            END;
        END LOOP;
    END;
    $$;
  sql
rescue ActiveRecord::StatementInvalid
  # ignore duplicate installs
end

#setup_data_migrations ⇒ Object 



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# File 'lib/data_migrations/setup.rb', line 3

def setup_data_migrations
  unless @setup
    install_upsert
    @setup = true
  end
end