The Parallel Query Option (PQO) is best used for systems where large, intense queries are being performed or where large amounts of data are being loaded, indexed and queried, such as in data warehous...
Processing SQL Statements The first time a select query is executed inside the Oracle engine, the statement will generally need to proceed through 4 different stages in order to return results back to...
Sometimes, data blocks are read in the database, and are infrequently reused. Often in a database we also have data blocks that are of frequent use (hot blocks). It is for these types of database bloc...
Adding Logfiles To add a redo log, the following command is used: ALTER DATABASE database name ADD LOGFILE THREAD y GROUP n (file specification, file specification) SIZE x; or: ALTER DATABASE dat...
How to Identify a Buffer Cache Chain Latch Problem Internally, Oracle uses various types of structures to control access to elements of the databases including latches and various types of enqueuein...
A sort area in memory is used to sort records before they are written out to disk. Increasing the size of this memory by increasing the value of the initialization parameters SORT_AREA_SIZE or PGA_AGG...
