Monday, 28 November 2011

Most frequently occuring problems in Oracle

What are the top ten problems most frequently occurring in the real world usage of Oracle databases?

The problems that I most frequently come across can be divided into two large categories: SPACE PROBLEMS and PERFORMANCE/MEMORY MAINTENANCE PROBLEMS.
In the space problems category, you will most likely find:
  • table reached its max extents
  • index reached its max extents
  • cannot extend tablespace because MAXSIZE reached or no space in drive
  • archiving error because ARCH process did not find space to copy the archived logs
In the performance problems category, you will most likely find:
  • problem in SHARE_POOL_SIZE (increase size)
  • number of processes reached its max
  • locking problems
  • ora-1555 snapshot too old (read consistency problems)
  • The big slow performance problem
Perhaps the most popular problem is when a programmer/manager comes to you and says something like "the application runs slowly -- you have a problem in the database! This is definitely the hardest problem to solve because there is no "cook book" solution.

*taken from