Latest Answer : PCTFREE : This clause is used for future updation, If you increase PCTFREE value, There will be less rows inserted in block ...
Export the user Perform import using the command imp system/manager file=export.dmp indexfile=newrite.sql. This will create all definitions into newfile.sql. Drop
Latest Answer : If its the same database use:alter table the_table move tablespace other_tablespace; alter index the_index rebuild tablespace other_tablespace; ...
PCTFREE parameter Row size also reduces no of rows per block.
Each block contains entries as followsFixed block headerVariable block headerRow Header,row date (multiple rows may exists)PCTEREE (% of free space for row updation in future)
Latest Answer : A block is divided into1. Header2.free space3.data spaceThe free space is in the middle shrinks as header and data space grow.Space usage in the data space :The data space is managed with 2 parametersa.pctused b.pctfreesuppose pctused=40 ...
This is used to reserve certain amount of space in a block for expansion of rows.
Calculate the total header sizeCalculate the available dataspace per data blockCalculate the combined column lengths of the average rowCalculate the total average row size.Calculate the average number
It is the set of before image data blocks that contain rows that are modified by a transaction.Each Rollback Segment entry
Latest Answer : A rollback segment entry consists of image of pre-update value, block address, data file number, transaction ID and transaction status (active or committed). A single rollback segment may contain several rollback entries and several active transactions. ...
When Segment is dropped.When Shrink (RBS only)When truncated (TRUNCATE used with drop storage option)
We should depend on export/import utility for backup/recovery (fully reliable) The tar command cannot be used for physical file backup, instead we can
The space used transaction entries and a deleted record does not become free immediately after completion due to delayed cleanout. Trailing nulls and length bytes are not stored. Inserts
