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When you changes the EXISTING VALUE to null, the On-validate field trigger will FIRE post change trigger will not fire. At the time of execute-query post-change trigger will fire, on-validate field trigger will not fire.

When you changes the Existing value to null, the On-validate field trigger will fire post change trigger will not fire. At the time of execute-query post-change trigger will fire, on-validate field trigger will not fire.

• LOGICAL BACKUPS
• Cold Backups
• HOT Backups (Archive LOG)

A flag to INDICATE WHETHER a read consistent VERSION of all the exported OBJECTS should be MAINTAINED.

A flag to indicate whether a read consistent version of all the exported objects should be maintained.

A flag to INDICATE WHETHER CONSTRAINTS on table NEED to be exported.

A flag to indicate whether constraints on table need to be exported.

A FLAG to INDICATE whether file CONTENT should be DISPLAYED or not.

A flag to indicate whether file content should be displayed or not.

A flag to INDICATE whether full databse export should be PERFORMED.

A flag to indicate whether full databse export should be performed.

A FLAG to indicate WHETHER GRANTS on database OBJECTS will be imported.

A flag to indicate whether grants on database objects will be imported.

A flag to indicate WHETHER GRANTS on databse objects will be EXPORTED or not. VALUE is 'Y' or 'N'.

A flag to indicate whether grants on databse objects will be exported or not. Value is 'Y' or 'N'.

A flag to indicate WHETHER import should import index on TABLES or not.

A flag to indicate whether import should import index on tables or not.

A FLAG to INDICATE WHETHER indexes on TABLES will be EXPORTED.

A flag to indicate whether indexes on tables will be exported.

A flag to INDICATE whether rows should be imported. If this is SET to 'N' then only DDL for database OBJECTS will be EXECUTED.

A flag to indicate whether rows should be imported. If this is set to 'N' then only DDL for database objects will be executed.

A flag to indicate whether STATISTICAL INFORMATION about the exported objects should be WRITTEN to export DUMP file.

A flag to indicate whether statistical information about the exported objects should be written to export dump file.

A FLAG to indicate whether the IMPORT should ignore errors ENCOUNTER when ISSUING CREATE commands.

A flag to indicate whether the import should ignore errors encounter when issuing CREATE commands.

A free EXTENT is a collection of CONTINUOUS free blocks in TABLESPACE. When a segment is dropped its EXTENTS are reallocated and are MARKED as free.

A free extent is a collection of continuous free blocks in tablespace. When a segment is dropped its extents are reallocated and are marked as free.

By QUERYING DBA_SEGMENT table/view.

By querying DBA_SEGMENT table/view.

• Calculate the TOTAL header size
• Calculate the AVAILABLE dataspace per DATA block
• Calculate the combined column lengths of the average row
• Calculate the total average row size.
• Calculate the average number rows that can fit in a block
• Calculate the number of BLOCKS and bytes required for the table.
• After arriving the calculation, add 10 % additional space to calculate the initial extent size for a WORKING table.

Changes made to entries are written to the on-line redo log files. So that they can be used in roll FORWARD operations during database RECOVERIES. Before writing them into the redo log files, they will FIRST BROUGHT to redo log buffers in SGA and LGWR will write into files FREQUENTLY. LOG_BUFFER parameter will decide the size.

Changes made to entries are written to the on-line redo log files. So that they can be used in roll forward operations during database recoveries. Before writing them into the redo log files, they will first brought to redo log buffers in SGA and LGWR will write into files frequently. LOG_BUFFER parameter will decide the size.

Cold BACKUP is taking backup of all PHYSICAL FILES after NORMAL shutdown of database. We need to take.

• All Data files.
• All Control files.
• All on-line REDO log files.
• The init.ora file (Optional)

Cold backup is taking backup of all physical files after normal shutdown of database. We need to take.

Create a database which implicitly creates a SYSTEM Rollback Segment in a SYSTEM tablespace. Create a Second Rollback Segment NAME R0 in the SYSTEM tablespace. Make NEW rollback segment available (After shutdown, modify init.ora file and START database) Create other tablespaces (RBS) for rollback segments. Deactivate Rollback Segment R0 and activate the newly CREATED rollback segments.

Create a database which implicitly creates a SYSTEM Rollback Segment in a SYSTEM tablespace. Create a Second Rollback Segment name R0 in the SYSTEM tablespace. Make new rollback segment available (After shutdown, modify init.ora file and Start database) Create other tablespaces (RBS) for rollback segments. Deactivate Rollback Segment R0 and activate the newly created rollback segments.

Database buffers are cache in the SGA USED to hold the data blocks that are read from the data segments in the database such as tables, indexes and CLUSTERS DB_BLOCK_BUFFERS parameter in INIT.ORA DECIDES the size.

Database buffers are cache in the SGA used to hold the data blocks that are read from the data segments in the database such as tables, indexes and clusters DB_BLOCK_BUFFERS parameter in INIT.ORA decides the size.

Database OVERALL physical architecture is maintained in a file called CONTROL file. It will be USED to maintain INTERNAL consistency and guide recovery operations. Multiple copies of control files are ADVISABLE.

Database overall physical architecture is maintained in a file called control file. It will be used to maintain internal consistency and guide recovery operations. Multiple copies of control files are advisable.

DICTIONARY CACHE is information about the databse OBJECTS stored in a DATA dictionary table.

Dictionary cache is information about the databse objects stored in a data dictionary table.

• Each block CONTAINS entries as follows
• Fixed block header
• Variable block header
• Row Header,row date (multiple ROWS may EXISTS)
• PCTEREE (% of free space for row updation in future)

FLAG to indicate whether EXPORT should COMPRESS FRAGMENTED segments into single extents.

Flag to indicate whether export should compress fragmented segments into single extents.

Flag to INDICATE whether table ROWS should be EXPORTED. If 'N' only DDL statements for the DATABASE objects will be CREATED.

Flag to indicate whether table rows should be exported. If 'N' only DDL statements for the database objects will be created.

For Incremental exports, the flag INDIRECTS WHETHER a record will be STORES data dictionary tables recording the export.

For Incremental exports, the flag indirects whether a record will be stores data dictionary tables recording the export.

• FREE extents cannot be MERGED together in Ver 6.0.
• Free extents are PERIODICALLY coalesces with the NEIGHBORING free extent in Ver 7.0.

• Full BACK - COMPLETE DATABASE
• Incremental - Only affected tables from last incremental date/full backup date.
• Cumulative backup - Only affected table from the last cumulative date/full backup date.

It is the SET of before IMAGE data blocks that contain rows that are MODIFIED by a transaction. Each Rollback Segment entry must be completed within one rollback segment. A single rollback segment can have multiple rollback segment ENTRIES.

It is the set of before image data blocks that contain rows that are modified by a transaction. Each Rollback Segment entry must be completed within one rollback segment. A single rollback segment can have multiple rollback segment entries.

Logical BACKUP involves reading a set of database records and writing them into a file. Export utility is USED for taking backup and IMPORT utility is used to RECOVER from backup.

Logical backup involves reading a set of database records and writing them into a file. Export utility is used for taking backup and Import utility is used to recover from backup.

NUMBER of times processes repeatedly query the dictionary table is called RECURSIVE HINTS. It is due to the data dictionary cache is too small. By INCREASING the SHARED_POOL_SIZE PARAMETER we can optimize the size of Data Dictionary Cache.

Number of times processes repeatedly query the dictionary table is called recursive hints. It is due to the data dictionary cache is too small. By increasing the SHARED_POOL_SIZE parameter we can optimize the size of Data Dictionary Cache.

PCTFREE PARAMETER. ROW size also reduces no of rows PER block.

PCTFREE parameter. Row size also reduces no of rows per block.

Process of having a COPY of redo LOG files is called mirroring. This can be achieved by creating GROUP of log files together, so that LGWR will AUTOMATICALLY WRITES them to all the members of the current on-line redo log group. If any one group fails then database automatically switch over to next group. It degrades performance.

Process of having a copy of redo log files is called mirroring. This can be achieved by creating group of log files together, so that LGWR will automatically writes them to all the members of the current on-line redo log group. If any one group fails then database automatically switch over to next group. It degrades performance.

Querying the DBA_ROLLBACK_SEGS view

• IN USE - Rollback Segment is on-line.
• AVAILABLE - Rollback Segment available but not on-line.
• OFF-LINE - Rollback Segment off-line
• INVALID - Rollback Segment Dropped.
• NEEDS RECOVERY - Contains data but need recovery or corupted.
• PARTLY AVAILABLE - Contains data from an UNRESOLVED transaction INVOLVING a distributed database.

Querying the DBA_ROLLBACK_SEGS view

RECORD LENGTH in BYTES.

Record length in bytes.

ROLLBACK SEGMENT DYNAMICALLY EXTENT to handle larger transactions entry loads. A single transaction may wipeout all available free space in the Rollback Segment TABLESPACE. This prevents other user using Rollback segments.

Rollback segment dynamically extent to handle larger transactions entry loads. A single transaction may wipeout all available free space in the Rollback Segment Tablespace. This prevents other user using Rollback segments.

SET TRANSACTION USE ROLLBACK SEGMENT rbs_name.

SET TRANSACTION USE ROLLBACK SEGMENT rbs_name.

Shadow set of DISKS save as a backup in the event of disk failure. In most Operating System if any disk failure occurs it automatically switchover to PLACE of failed disk. Improved performance because most OS support VOLUME shadowing can direct file I/O request to use the shadow set of files instead of the main set of files. This reduces I/O load on the main set of disks.

Shadow set of disks save as a backup in the event of disk failure. In most Operating System if any disk failure occurs it automatically switchover to place of failed disk. Improved performance because most OS support volume shadowing can direct file I/O request to use the shadow set of files instead of the main set of files. This reduces I/O load on the main set of disks.

SHUTDOWN the database Copy one of the existing CONTROL FILE to new location Edit CONFIG ora file by adding new control file. name RESTART the database.

Shutdown the database Copy one of the existing control file to new location Edit Config ora file by adding new control file. name Restart the database.

• SYSTEM - Data dictionary tables.
• DATA - Standard operational tables.
• DATA2- STATIC tables USED for standard OPERATIONS
• INDEXES - Indexes for Standard operational tables.
• INDEXES1 - Indexes of static tables used for standard operations.
• TOOLS - Tools table.
• TOOLS1 - Indexes for tools table.
• RBS - Standard Operations Rollback Segments,
• RBS1,RBS2 - Additional/Special Rollback segments.
• TEMP - Temporary purpose tablespace
• TEMP_USER - Temporary tablespace for users.
• USERS - User tablespace.

TAKING BACKUP of archive log files when database is open. For this the ARCHIVELOG mode should be enabled. The FOLLOWING files need to be backed up. All data files. All Archive log, redo log files. All control files.

Taking backup of archive log files when database is open. For this the ARCHIVELOG mode should be enabled. The following files need to be backed up. All data files. All Archive log, redo log files. All control files.

The DATA DICTIONARY CACHE is stored in an area in SGA called the Shared SQL Pool. This will allow sharing of parsed SQL statements among concurrent USERS.

The data dictionary cache is stored in an area in SGA called the Shared SQL Pool. This will allow sharing of parsed SQL statements among concurrent users.

The NAME of the FILE from which IMPORT should be PERFORMED.

The name of the file from which import should be performed.

Type export should be performed COMPLETE,CUMULATIVE,INCREMENTAL. List the sequence of events when a large transaction that EXCEEDS beyond its optimal value when an entry wraps and causes the rollback segment toexpand into ANOTION Completes. E. will be written.

Type export should be performed COMPLETE,CUMULATIVE,INCREMENTAL. List the sequence of events when a large transaction that exceeds beyond its optimal value when an entry wraps and causes the rollback segment toexpand into anotion Completes. e. will be written.

We can plan the storage for a table as how much initial EXTENTS are REQUIRED, how much can be extended next, how much % should leave FREE for MANAGING row updations etc.,

We can plan the storage for a table as how much initial extents are required, how much can be extended next, how much % should leave free for managing row updations etc.,

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 USE DD command which is LESS flexible and has limited recoveries.

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 use dd command which is less flexible and has limited recoveries.

YES. The advantages over FILE system FILES. I/O will be improved because Oracle is bye-passing the kernnel which writing into DISK. Disk CORRUPTION will be very less.

Yes. The advantages over file system files. I/O will be improved because Oracle is bye-passing the kernnel which writing into disk. Disk Corruption will be very less.

& PHYSICAL PAGE no.

& physical page no.

• .FMB - FORM MODULE BINARY
• .fmx - form module executable

• .MMB,
• .MMX