You can use Oracle Enterprise Manager Database Express (EM Express) to set a datafile for a smallfile tablespace to automatically extend when it reaches its size limit. The following instructions assume that the datafile was previously not an autoextending datafile.
To set a datafile to automatically extend:
In EM Express, from the Storage menu, select Tablespaces.
The Tablespaces page appears.
For a smallfile tablespace, select a datafile for which you want to enable autoextend, and then from the Actions menu, select Edit Auto Extend.
The Auto Extend Setting of Datafile page appears.
Complete the following steps:
Select Auto Extend.
Set a suitable increment, such as 10 MB.
This is the amount of disk space that is added to the data file when it needs more storage space.
For Maximum File Size, enter a value in KB, MB, GB, or TB, depending on available storage.
Click OK.
A confirmation message appears.
You can perform these steps for all the datafiles in a smallfile tablespace to set all of the datafiles to automatically extend.