SELECT CONCAT('ALTER TABLE ', table_schema,'.', TABLE_NAME,' ADD COLUMN `hash` VARCHAR(50) NULL DEFAULT UUID() AFTER ', first_column, ';') AS ddl
FROM (
SELECT
(
SELECT `COLUMN_NAME`
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`=t.TABLE_SCHEMA AND `TABLE_NAME`=t.TABLE_NAME
LIMIT 1
) AS 'first_column',
t.*
FROM
information_schema.tables t
WHERE table_schema = 'your_table_name' AND table_type = 'base table'
) AS x;