Oracle Basic SQL 006 Study Tips
list employee infor and list the manager’s name.
Oracle Basic SQL 005 Study Tips
Oracle Basic SQL 004 Study Tips
Oracle Basic SQL 003 Study Tips
HASH JOIN SEMI
Oracle Basic SQL 002 Study Tips
Oracle Basic SQL 001 Study Tips
null first/null last
case when
Oracle awrinfo sql Tips
This script will output general Automatic Workload Repository(AWR) information such as the size, data distribution, etc. in AWR and SYSAUX. The intended use of this script is for diagnosing abnormalities in AWR and not for diagnosing issues in the database instance. Please look at addmrpt.sql and awrrpt.sql for diagnosing database issues.
Oracle SYSAUX huge space Tips
If SYS.WRI$_ADV_OBJECTS is one of the largest objects, cancel or delete old segment adviser tasks.
The task ‘Get shrink advice based on object growth trend’ in particular can use a lot of space.
If there is space pressure, cancel and delete these tasks in Grid/Database Control via Performance> Advisors Home or manually using the DBMS_ADVISOR package.
Oracle rman catalog Tips
Error:
Oracle error from recovery catalog database: ORA-00955: name is already used by an existing object
Oracle error from recovery catalog database: ORA-00942: table or view does not exist
Fix:
drop catalog and recreate catalog.
Oracle SQLcl Tips
Oracle SQLcl (SQL Developer Command Line), a Java-based command-line interface for Oracle Database.
Using SQLcl, you can execute SQL and PL/SQL statements interactively or as as a batch file.
SQLcl provides inline editing, statement completion, command recall, and also supports existing SQL*Plus scripts.