As the Oracle database grows, the existing data files in the tablespace will fill up.
In such a case, you will need to add a new data file to the tablespace so that the database can continue to grow.
With the command below you can add a new data file to the xyz tablespace.
With this script, you will add a data file in the “+DATA” Diskgroup on ASM that will grow to 1024 MB when needed with a starting size of 100 MB.
ALTER TABLESPACE xyz ADD DATAFILE
'+DATA' SIZE 100M AUTOEXTEND ON NEXT 1024M MAXSIZE UNLIMITED;
You can read the article named “How To Create Tablespace On Oracle” about how to create Oracle Tablespace.