Solution to oracle tablespace not enough

execute the following commands by using system account login oracle:

　　>sqlplus system/111111@localhost:1522/xe;

SQL*Plus: Release 12.1.0.1.0 Production on Tue Sep 22 20:16:29 2015

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Connected to:
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production

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 1.the below command to display the current size of tablespace

　　>select t.tablespace_name,round(SUM(bytes/(1024*1024)),0) ts_size from dba_tablespaces t,dba_data_files d where t.tablespace_name=d.tablespace_name  group by t.tablespace_name;

TABLESPACE_NAME           TS_SIZE
------------------------------ ----------
SYSAUX                      680
UNDOTBS1                  510
USERS                      100
SYSTEM                      600

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2.use the below command to display the path of tablespace that will be used in command to modify the size of tablespace.

　　>select file_name,tablespace_name from dba_data_files;

FILE_NAME                                                                                       TABLESPACE_NAME
---------------------------------------------------------------------------　　　  -----------------------------------
/u01/app/oracle/oradata/XE/system.dbf                                       　　　　SYSTEM

3.the last command is to expand the size of current tablespace.
　　> alter database datafile '/u01/app/oracle/oradata/XE/system.dbf' resize 5600M;

Database altered.

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