WordPress ACF rename field after converting to repeater

acf-convert-field-to-repeater.sql

-- This transaction converts previous acf file field named
-- 'course_field_schedule_file' into acf repeater field
-- containing single file field
START TRANSACTION;
SET @repeater_name = 'course_field_schedule_file';
SET @field_name = 'file';
INSERT INTO
  wp_postmeta (post_id, meta_key, meta_value)
SELECT post_id, CONCAT(@repeater_name, '_0_', @field_name), meta_value FROM wp_postmeta WHERE meta_key = @repeater_name AND meta_value != '';

UPDATE wp_postmeta
SET meta_value = 1
WHERE meta_id IN (
  SELECT * FROM (SELECT meta_id FROM wp_postmeta WHERE meta_key = @repeater_name AND meta_value != '') AS p
);
COMMIT;

-- Disclaimer: Use at your own risk! NO WARRANTY! Make backup before use and test on local environment first! :-)