方法一：使用sqlplus
64位：
[Oracle@qs-wg-db2 ~]$ sqlplus / as sysdba;
SQL*Plus:Release 10.2.0.5.0 - Productionon Sun Sep 25 08:57:22 2011
Copyright(c) 1982, 2010, Oracle. All Rights Reserved.
Connectedto:
OracleDatabase 10g Enterprise EditionRelease 10.2.0.5.0 - 64bit Production
Withthe Partitioning, OLAP, Data Miningand Real Application Testing options
SQL>
如果是64位，用sqlplus 连上之后会显示具体的位数信息，32位则不会显示。
32位：
C:UsersAdministrator.DavidDai>sqlplus/as sysdba;
SQL*Plus:Release 11.2.0.1.0 Production onSun Sep 25 08:55:48 2011
Copyright(c) 1982, 2010, Oracle. All rights reserved.
Connectedto:
OracleDatabase 11g Enterprise EditionRelease 11.2.0.1.0 - Production
Withthe Partitioning, OLAP, Data Miningand Real Application Testing options
方法二：查看v$version视图
32位：
SQL>select * from v$version;
BANNER
--------------------------------------------------------------------------
OracleDatabase 11g Enterprise EditionRelease 11.2.0.1.0 - Production
PL/SQLRelease 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
TNSfor 32-bit Windows: Version 11.2.0.1.0- Production
NLSRTLVersion 11.2.0.1.0 - Production
64位：
SQL>select * from v$version;
BANNER
----------------------------------------------------------------
OracleDatabase 10g Enterprise EditionRelease 10.2.0.5.0 - 64bi
PL/SQLRelease 10.2.0.5.0 - Production
CORE 10.2.0.5.0 Production
TNSfor Linux: Version 10.2.0.5.0-Production
NLSRTLVersion 10.2.0.5.0 – Production
和第一种方法一样，64位会显示具体的位数信息，32位不会显示。
方法三：查看v$sql 视图
32位：输出为8位16进制数
SQL>select address from v$sql whererownum<2;
ADDRESS
--------
B50ACCAC
64位：输出为16位16进制数
SQL>select address from v$sql whererownum<2;
ADDRESS
----------------
0000000196FDF7D8