ora-01440: To reduce the precision or scale, the column to be modified must be empty

-Due to changes in business requirements, the PRODUCTPRCIE structure of the Oracle Database ProductInfo table needs to be modified. To modify the table structure, you must be able to modify the table structure in the case of empty tables.          Specific steps:--1, view productinfo table structure--2, ProductInfo table ProductID Backup CREATE TABLE Productinfo_bak      As SELECT * from ProductInfo;      --3, delete the data in the ProductInfo table delete from ProductInfo;      --4, modify table structure ALTER TABLE ProductInfo modify Productprcie number (10,2); --5, restore table structure INSERT INTO ProductInfo select * from Productinfo_bak;