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create table table1(col1 varchar(50), col2 varchar(50));
insert into table1 values('AB','AB123');
insert into table1 values('BC123','SG');
insert into table1 values('BG274','HF');
insert into table1 values('DC','DG789');
insert into table1 values('DG156','HD');
select col1 from table1 where col1 regexp '[A-Za-z][0-9]'
union
select col2 from table1 where col2 regexp '[A-Za-z][0-9]'
| col1 |
|---|
| BC123 |
| BG274 |
| DG156 |
| AB123 |
| DG789 |