Oracle's frequently asked questions and solutions

Just contact Oracle, in the learning process encountered a lot of problems, this article will collect my problems and how to solve.

Error one: Ora-28009:connection as sys should be as SYSDBA
Workaround: User name: sys, password: password, host string: ORCL as SYSDBA (the global database I set is named ORCL)

Error Two: ora-28000:the account is locked
Workaround:
(1) Conn Sys/sys as SYSDBA; Log in as a DBA
(2) Alter user Scott account unlock;//then unlock
(3) Conn Scott/tiger//Popup A Password Change dialog box, modify the password can be
Cause: Oracle 10 default Scott cannot log on

Error Three: Ora-01861:literal does not match format string

WORKAROUND: Alter session set Nls_date_format = ' Yyyy-mm-dd hh24:mi:ss '; Modifying the Oracle Default time format

Reason: Oracle default time Format ' dd-mm month-yy '

Supplement: To_char (Sysdate, ' yyyy-mm-dd HH12:MI:SS AM ') 12-hour system
To_char (sysdate, ' yyyy-mm-dd HH24:MI:SS AM ') 24-hour system
To_date (' 1986-4-3 ', ' yyyy-mm-dd ')

Error four : Error-ora-12560:tns:protocol adapter Error
WORKAROUND: The listener service is not up. Open Oracle Services in the service

Error Five: System administrator password forgotten
Workaround: Open cmd, enter Sqlplus/nolog, enter Conn/as SYSDBA; Enter alter user SYS identified by new password (note that the password starts with a letter)

Change Password: alter user identified by values ' password ';

Oracle Paging

The first type: SELECT * FROM (select A1.*,rownum rn from (select query column from table where condition Order by column) A1 whererownum<10) where rn>6;

Second type: Select query column from table where rowID in (select Rid from (select RowNum rn,rid from (select rowID RID from table order by column) where R OWNUM<10) where rn>6) order by column;