MySQL 5.5

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select version();

version()

5.5.62

create table your_table (column_name varchar(50));

insert into your_table values 
('0123458921'),
('12344asd12341'),
('012-38jh213a'),
('12398798797')
SELECT * 
FROM your_table
WHERE column_name REGEXP '^[0-9]+$' and length(column_name) in (10,11)

column_name

0123458921

12398798797