Hi All,
I have an requirement, where i need to convert my existing colum datatype to new datatype (ie From number(3) to Varchar(3).
i followed the steps
1. Create a new column A with datatype of varchar2
2. Copying the existing column value to new column A
3. disabling /dropping the constraints on existing colum
4. updating the existing column to null
5. modifying the existing column datatype ( from number to varchar2)
6. copying the values from new column A to existing column
7. dropping the column A
8. enabling the constraints.
But it takes more time in step2 (around 50+ mins )
can you suggest is there any better way to change the column datatype ?
Thanks in advance.