在10g以后，一般情况下环境变量中没有必要设置LD_LIBRARY_PATH，但是一旦将ORACLE_HOME迁移到其他目录，则环境变量中还需要添加这个变量。
Linux和Unix支持TAR方式迁移ORACLE_HOME，如果有需要将ORACLE_HOME放到其他路径下，那么一般都会使用tar的方式将整个路径拷贝到目标目录。
但是迁移后，如果直接尝试sqlplus启动，可能报错：
[orat3@hpserver2 ~]$ sqlplus / as
sysdba
sqlplus: error while loading shared libraries: libsqlplus.so: cannot open
shared object file: No such file or directory
而设置LD_LIBRARY_PATH后，问题解决：
[orat3@hpserver2 ~]$ export
LD_LIBRARY_PATH=$ORACLE_HOME/lib
[orat3@hpserver2 ~]$ sqlplus / as sysdba
SQL*Plus: Release 10.2.0.4.0 -
Production on Sun Mar 18 16:10:57 2012
Copyright (c) 1982, 2007, Oracle.
All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL>
还有一种类似的错误：
[orat0@hpserver2 ~]$ sqlplus / as
sysdba
SQL*Plus: Release 10.2.0.5.0 -
Production on Sun Mar 18 16:12:03 2012
Copyright (c) 1982, 2010, Oracle.
All Rights Reserved.
oracleorcl10g: error while loading
shared libraries: libskgxp10.so: cannot open shared object file: No such file
or directory
ERROR:
ORA-12547: TNS:lost contact
Enter user-name:
oracleorcl10g: error while loading shared libraries: libskgxp10.so: cannot open
shared object file: No such file or directory
ERROR:
ORA-12547: TNS:lost contact
Enter user-name:
oracleorcl10g: error while loading shared libraries: libskgxp10.so: cannot open
shared object file: No such file or directory
ERROR:
ORA-12547: TNS:lost contact
SP2-0157: unable to CONNECT to
ORACLE after 3 attempts, exiting SQL*Plus
[orat0@hpserver2 ~]$ export LD_LIBRARY_PATH=$ORACLE_HOME/lib
[orat0@hpserver2 ~]$ sqlplus / as sysdba
SQL*Plus: Release 10.2.0.5.0 -
Production on Sun Mar 18 16:12:18 2012
Copyright (c) 1982, 2010, Oracle.
All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL>
错误的表相虽然不同，但是解决方法是相同的。