create a backup table with million records
In case you won't need the data immediately, you can try extracting table structure, then rename it to backup, and create a new table with the same structure and name.

ALTER TABLE table_name RENAME TO new_table_name;


This will show the table structure. you can use the result to create new table.

&gt;describe table_name


many suggestions are out there to copy by the select statement onstackoverflow. one is:

create table table_name as select * from table_name_oldd where 1=0;


It creates structure but won't copy any value because the condition is false.