Row chaining occurs when a row can't physically fit into an Oracle block. Another block is required to store the remainder of the row. Chaining can cause serious performance problems and is especially...
Identify Contention The following query determines the miss ratio and the "immediate" miss ratio for redo log latches. Col MISS_RATIO format 999.99Col IMM_MISS_RATIO format 999.99 SELECT substr(ln.na...
This wait event only occurs when Flashback Database is turned on. A session waits for recovery writer (RVWR) to write flashback data to the flashback logs on disk because the buffers are full. Until R...
A direct path read I/O operation reads data into the session's PGA instead of the SGA. Direct read I/Os may be performed in synchronous or asynchronous mode, depending on the platform and the value of...
The db file scattered read wait event is similar to the db file sequential read, except that the session is waiting for a multi-block I/O read request to complete. The db file scattered read waits are...
Ever had the worry that when you connect to a database to send some data to it, that some eavesdropper on the network might just be waiting to catch all your passwords (Oracle sends passwords in plain...
