Oracle updating records within same cursor
All the extents that an object takes when grouped together are considered the segment of the database object.
Both the truncate and delete command have the desired outcome of getting rid of all the rows in a table.
The benefit of taking a cold backup is that it is typically easier to administer the backup and recovery process.In addition, since you are taking cold backups the database does not require being in archive log mode and thus there will be a slight performance gain as the database is not cutting archive logs to disk.A data block is the smallest unit of logical storage for a database object.Expected answer: Use the %ISOPEN cursor status variable. For all parameters, their value and whether or not the current value is the default value, look in the v$parameter view. Describe hit ratio as it pertains to the database buffers. s default setting The IMPORT IGNORE option tells import to ignore "already exists" errors. If the DEFAULT and TEMPORARY tablespace clauses are left out of a CREATE USER command what happens? Why The user is assigned the SYSTEM tablespace as a default and temporary tablespace. However, for the enable clause you must specify the USING INDEX and TABLESPACE clause for primary keys. What happens if a primary key constraint is disabled and then enabled without fully specifying the index clause The index is created in the user? The quick and dirty way is to look at the number of blocks the table is actually using and ratio the number of rows in the table to its number of blocks against the number of expected rows. How can you find out how many users are currently logged into the database?What is the difference between instantaneous and cumulative hit ratio and which should be used for tuning The hit ratio is a measure of how many times the database was able to read a value from the buffers verses how many times it had to re-read a data value from the disks. If it is not specified the tables that already exist will be skipped. You have a rollback segment in a version 7.2 database that has expanded beyond optimal, how can it be restored to optimal Use the ALTER TABLESPACE ..... This is bad because it causes user objects and temporary segments to be placed into the SYSTEM tablespace resulting in fragmentation and improper table placement (only data dictionary objects and the system rollback segment should be in SYSTEM). What are some of the Oracle provided packages that DBAs should be aware of Oracle provides a number of packages in the form of the DBMS_ packages owned by the SYS user. s default tablespace and all sizing information is lost. t store this information as a part of the constraint definition, but only as part of the index definition, when the constraint was disabled the index was dropped and the information is gone. (On UNIX) When should more than one DB writer process be used? How can you find their operating system id There are several ways.