SELECT CONCAT
(
'ALTER TABLE ',
t1.TABLE_SCHEMA,
'.',
t1.table_name,
' MODIFY ',
t1.column_name,
' ',
t1.data_type,
'(' ,
CHARACTER_MAXIMUM_LENGTH,
')',
' CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;'
)
FROM
information_schema.columns t1
WHERE t1.TABLE_SCHEMA like 'omtest' AND t1.COLLATION_NAME IS NOT NULL AND t1.COLLATION_NAME NOT IN ('utf8mb4_unicode_ci')
AND table_name = 'emails';