Changing CLOB fields to VARCHAR2 fields

To change a CLOB field to a VARCHAR field in Oracle create a

temporary column (varchar) to hold the cast. Execute the following

command and then rename drop the old one and rename the new column:

UPDATE table SET tempcol = dbms_lob.substr(column, 10, 1)

Where 10 is the length of the column and 1 is the starting position of th

CLOB string.

Increasing tablespace size, Oracle

Checking sizes:
SELECT * FROM DBA_DATA_FILES;

Resizing:
ALTER DATABASE DATAFILE ‘D:\ORACLEXE\ORADATA\XE\USERS.DBF‘ RESIZE 200M;

Addind Datafile to existing Tablespace:
ALTER TABLESPACE USERS ADD DATAFILE ‘D:\ORACLEXE\ORADATA\XE\USERS_2.DBF‘ SIZE 50M;