Short Question for Oracle,

3. What is Schema ?

      The set of objects owned by user account is called the schema

      4. What is an Index ? How it is implemented in Oracle Database ?

      An index is a database structure used by the server to have direct access 

      of a row in a table.

      An index is automatically created when a unique or primary key constraint 

      clause is specified in create table command (Ver 7.0)

      5. What is clustres ?

      Group of tables physically stored together because they share common 

      columns and are often used together is called Clusters.

      6. What is a cluster key ?

      The related columns of the tables are called the cluster key. The cluster 

      key is indexed using a cluster index and its value is stores only once for 

      multiple tables in the cluster.

      7. What are the basic element of Base configuration of an oracle Database 

      It consists of

      one or more data files

      one or more control files

      two or more redo log files

      The database contains

      Multiple users/schemas

      one or more rollback segments

      one or more tablespaces

      Data dictionary tables

      User objects (tables,indexes,views etc)

      The server that access the database consists of

      SGA (Database buffer, Dictionary Cache Buffers, redo log buffers,Shared 

      SQL pool)

      SMON

      PMON

      LGWR

      DBWR

      ARCH

      CKPT

      RECO

      Dispatcher

      User process with associated PGA

      8. What is deadlock ? Explain.

      Two processes waiting to update the rows of a table which are locked by 

      the other process then deadlock arises.

      In a database environment this will often happen because of not issuing 

      proper row lock commands. Poor design of front-end application may cause 

      this situation and the performance of server will reduce drastically.

      These locks will be released automatically when a commit/rollback 

      operation performed or any one of this processes being killed externally.

     3.2 Memory Management

      9. What is SGA ? How it is different from Ver 6 and Ver 7 ?

      The System Global Area in a Oracle database is the area in memory to 

      facilitates the transfer of information between users. It holds the most 

      recently requested structural information about the database.

      The structure is Database buffers, Dictionary Cache, Redo Log Buffer and 

      Shared SQL pool (Ver 7) area.

      10. What is Shared SQL pool ?

      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.

      11. What is meant by Program Global Area (PGA) ?

      It is area in memory that is used by a Single Oracle User process.

      12. What is a data segment ?

      Data segment are the physical areas within a database block in which the 

      data associated with tables and clusters are stored.

      13. What are the factors causing the reparsing of SQL statements in SGA ?

      Due to insufficient Shared SQL pool size

      Monitor the ratio of the reloads takes place while executing SQL 

      statements. If the ratio is greater that 1 then increase the 

      SHARED_POOL_SIZE.

      3.3 Logical & Physical Architecture of Database

      14. What is Database Buffers ?

      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.

      15. What is dictionary cache ?

      Dictionary cache is information about the database objects stored in a 

      data dictionary table.

      16. What is meant by recursive hits ?

      Number of times processes repeatedly query the dictionary table is called 

      recursive hits. 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.

      17. What is meant by redo log buffer ?

      Changes made to entries are written to the on-line redo log files so that 

      they can be used in roll forward operation 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.

      18. How will you swap objects into a different table space for an existing 

      database ?

      Export the user

      Perform import using the command imp system/manager file=export.dp 

      indexfile=newfile.sql. This will create all definitions into newfile.sql.

      Drop necessary objects.

      Run the script newfile.sql after altering the tablespaces.

      Import from the backup for the necessary objects.

      19. List the Optimal Flexible Architecture (OFA) of Oracle database ? or

      How can we organise the tablespaces in Oracle database to have maximum 

      performance ?

      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 - Tool 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 tablespaces.

      20. How will you force database to use particular rollback segment ?

      SET TRANSACTION USE ROLLBACK SEGMENT rbs_name

      21. What is meant by free extent ?

      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.

      22. How free extents are managed in Ver 6 and Ver 7. ?

      Free extents cannot be merged together in Ver 6.0

      Free extents are periodically coalesces with the neighboring free extent 

      Ver 7.0.

      23. Which parameter in Storage clause will reduce no of rows per block ?

      PCTFREE parameter

      Row size also reduces no of rows per block.

      24. What is significance of having storage clause ?

      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.

      25. How does space allocation take place within a block ?

      Each block contains entries as follows :

      Fixed block header

      Variable block header

      Row header, row date (Multiple rows may exists)

      PCTFREE (% of free space for row updation in future)

      26. What is the role of PCTFREE parameter is Storage clause ?

      This is used to reserve certain amount of space in a block for expansion 

      of rows.

      27. What is the OPTIMAL parameter ?

      It is used to set the optimal length of rollback segment.

      28. What is the functionality of SYSTEM tablespace ?

      To manage the database level of transactions such as modifications of the 

      data dictionary table that record information about the free space usage.

      29. How will you create multiple rollback segments in a database ?

      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 tablespace (RBS) for rollback segments.

      Create additional Rollback segment in tablespace (RBS)

      Deactivate Rollback Segment R0 and activate the newly created rollback 

      segments.

      30. How the space utilisation takes place within rollback segments ?

      It will try to fit the transaction in a cyclic fashion to all existing 

      extents. Once it found an extent is in use then it forced to acquire a new 

      extent. (No of extents is based on the OPTIMAL size).

      31. Why query fails sometimes ?

      Rollback segment dynamically extent to handle larger transactions entry 

      loads.

      A single transaction may wipeout all available free space in the Rollback 

      Segment Table space. This prevents other user using Rollback segment.

      32. How will you monitor the space allocation ?

      By querying DBA_SEGMENT table/View

      33. How will you monitor rollback segment status ?

      Querying the DBA_ROLLBACK_SEGS view

      The status available as follows :

      IN USE - Rollback Segment is on-line

      AVAILABLE - Rollback Segment available bur not on-line

      OFF-LINE - Rollback Segment us off-line

      INVALID - Rollback Segment dropped

      NEEDS RECOVERY - Contains data but need recovery or corrupted

      PARTLY AVAILABLE - Contains data from an unresolved transaction involving 

      a distributed database

      34. List the sequence of events when a large transaction that exceeds 

      beyond its optimal value when an entry wraps and causes the rollback 

      segment to expand into another extend.

      Transaction Begins

      An entry is made in the RBS header for new transactions entry

      Transaction acquired blocks in an extent of RBS

      The entry attempts to wrap into second extent. None is available. So that 

      the RBS must extent.

      The RBS checks to see if it is oldest inactive segment

      Oldest inactive segment is eliminated

      RBS extends

      The Data dictionary table for space management are updated

      Transaction Completes.

      35. How can we plan storage for very large tables ?

      Limit the number of extents in the table

      Separate the Table from its indexes

      Allocate sufficient temporary storage

      36. How will you estimate the space required by non-clustered tables ?

      Calculate the total block header size

      Calculate the available data space per block

      Calculate the combined column length 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 the additional space to calculate the 

      initial extent size for working area

      37. Is it possible to use raw devices as data file and what is the 

      advantages over file system files ?

      Yes.

      The advantages over file system files :

      I/O will be improved because Oracle is bye-passing the kernal while 

      writing into disk.

      Disk Corruption will be very less.

      38. What is a control file ?

      Database's 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.

      39. How to implement the multiple control files for an existing 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

      40. What is meant by Redo Log file mirroring ? How it can be achieved ?

      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.

      41. What is advantage of having disk shadowing/Mirroring ?

      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 of 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.

      42. What is use of rollback segment in Database ?

      They allow the database to maintain read consistency between multiple 

      transactions.

      43. What is a Rollback segment entry ?

      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.

      44. What a hit ratio ?

      It is a measure of well the data cache buffer is handling requests for 

      data.

      Hit Ratio = (Logical Reads - Physical reads - Hit Misses) / Logical reads.

      45. When will be a segment released ?

      When Segment is dropped.

      When Shrink (RBS only)

      When truncated (TRUNCATE used with drop storage option)

      46. What are disadvantages of having raw devices ?

      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.

      47. List the factors that can affect the accuracy of the estimations ?

      The space used transaction entries and deleted records does not become 

      free immediately after completion due to delayed cleanout.

      Trailing nulls and length bytes are not stored.

      Inserts of, updates to, and deletes of rows as well as columns larger than 

      a single data block, can cause fragmentation and chained row pieces.

      3.4 Database Security & Administration

      48. What is user account in Oracle database ?

      An user account is not a physical structure in Database but it is having 

      important relationship to the objects in the database and will be having 

      certain privileges.

      49. How will you enforce security using stores procedures ?

      Don't grant user access directly to tables within application

      Instead grant the ability to access the procedures that access the tables

      When procedure executed it will execute the privilege of procedures owner. 

      Users cannot access tables except via the procedure.

      50. What are the dictionary tables used to monitor a database spaces ?

      DBA_FREE_SPACE

      DBA_SEGMENTS

      DBA_DATA_FILES

      51. What are responsibilities of a Database Administrator ?

      1. Installing and upgrading the Oracle Server and application tools

      2. Allocating system storage and planning future storage requirements for 

      the database system.

      3. Managing primary database structures(tablespaces)

      4. Managing primary objects (table,views,indexes)

      5. Enrolling users and maintaining system security

      6. Ensuring compliance with Oracle license agreement

      7. Controlling and monitoring user access to the database

      8. Monitoring and optimising the performance of the database

      9. Planning for backup and recovery of database information

      10. Maintain archived data on tape

      11. Backing up and restoring the database

      12. Contacting Oracle Corporation for technical support

      52. What are requirements one should fulfill to connect to ORACLE as 

      internal?

      Operating system account has the operating system privileges that allow 

      you to connect

      One should be authorised to connect as internal

      Database has a password for internal connections, and you know the 

      password must use a dedicated server

      53. What are the roles and user accounts created automatically with the 

      database ?

      DBA role - Contains all database system privileges

      SYS user account - The DBA role will be assigned to this account. All of 

      the base tables and views for the database's dictionary are store in this 

      schema and are manipulated only by ORACLE.

      SYSTEM user account - It has all the system privileges for the database 

      and additional tables and views that display administrative information 

      and internal tables and views used by oracle tools are created using the 

      username.

      54. What are the database administrators utilities available ?

      SQL*DBA - This allows DBA to monitor and control an ORACLE database.

      SQL*Loader - It loads data from standard operating system files (Flat 

      files) into ORACLE database tables.

      EXPORT(exp) and IMPOER (imp) utilities allow you to move existing data in 

      ORACLE format to and from ORACLE database.

      55. What are the minimum parameters should exist in the parameter file 

      (init.ora) ?

      DB_NAME - Must set to a text string of not more that 8 characters and it 

      will be stored inside the datafiles, redo log files and control file while 

      database creation.

      DB_DOMAIN - It is string that specifies the network domain where the 

      database is created. The global database name is identified by setting 

      these parameters (DB_NAME & DB_DOMAIN)

      CONTROL_FILES - List of control filenames of the database. If name is not 

      mentioned then default name will be used.

      DB_BLOCK_SIZE - The default data block size and is operating system 

      dependent. It cannot be changed after database creation except by 

      re-creating the database.

      DB_BLOCK_BUFFERS - The maximum number of operating system processes that 

      can be connected to ORACLE concurrently. The value should be 5 (background 

      process) and additional 1 for each user.

      ROLLBACK_SEGMENTS - List of rollback segments an ORACLE instance acquires 

      at database startup.

      Also optionally LICENSE_MAX_SESSIONS,LICENSE_SESSION_WARNING and 

      LICENSE_MAX_USERS.

      56. What is a trace file and how it is created ?

      Each server and background process can write an associated trace file. 

      When an internal error is detected by a process or user process, it dumps 

      information about the error to its trace. This can be used for tuning the 

      database.

      57. What are roles ? How can we implement roles ?

      Roles are easiest way to grant and manage common privileges needed by 

      different groups of database users.

      Creating roles and assigning privies to roles.

      Assign each role to group of users. This will simplify the job of 

      assigning privileges to individual users.

      58. What are the steps to switch a database's archiving mode between 

      NOARCHIEVELOG and ARCHIVELOG mode ?

      1. Shutdown the database instance

      2. Backup the database

      3. Perform any operating system specific steps (optional)

      4. Start up a new instance and mount but do not open the database

      5. Switch the database's archiving mode.

      59. How can you enable automatic archiving ?

      Shut the database

      Backup the database

      Modify/Include LOG_ARCHIVE_START = TRUE in init.ora file

      Start up the database

      60. How can we specify the Archived log file name format and destination ?

      By setting the following values in init.ora file

      LOG_ARCHIVE_FORMAT = arch%S/s/T/t.arc (%S - Log sequence number and is 

      zero left-paded, %s - Log sequence number not paded, %T - Thread number 

      left-zero-paded and %t - Thread number not paded). The file name created 

      is arch0001.arc %S is used.

      LOG_ARCHIEVE_DEST = path

      Shut the database and change these parameters in init.ora files.

      61. What is the user of ANALYZE command ?

      To perform one of these function on an index, table, or cluster :

      to collect statistics about object used by the optimizer and store them in 

      the data dictionary.

      to delete statistics about the object from the data dictionary

      to validate the structure of the object

      to identify migrated and chained rows of the table or cluster.

      3.5 Managing Distributed Databases

      62. How can we reduce the network traffic ?

      Replication of data in distributed environment

      Using snapshots to replicate data

      Using remote procedure calls.

          63. What is a snapshot ?

      Snapshot is an object used to dynamically replicate data between 

      distributed databases at specified time intervals. In ver 7.0 they are 

      read only.

      64. What are the various type of snapshots ?

      Simple and Complex.

      65. Differentiative simple and complex, snapshots

      A simple snapshot is based on a query that does not contains GROUP BY 

      clauses, CONNECT by clauses, JOINs, Subquery or a set of operations.

      A complex snapshots contain at least any one of the above.

      66. What is dynamic data replication ?

      Updating or inserting records in remote database through database 

      triggers. It may fail if remote database is having any problem.

      67. How can you enforce referential integrity in snapshots ?

      Time the references to occur when master tables are not in use.

      Perform the references manually immediately after locking the master 

      tables.

      We can join tables in snapshots by creating a complex snapshot that will 

      be based on the master tables.

      68. What are the options available to refresh snapshots ?

      COMPLETE - Tables are completely regenerated using the snapshot's query 

      and the master tables every time the snapshot referenced.

      FAST - If simple snapshot used then a snapshot log can be used to send 

      only the changes to the snapshot tables.

      FORCE - The default value. If possible it performs a FAST refresh; 

      Otherwise it will perform a COMPLETE refresh.

      69. What is a snapshot tag ?

      It is a table that maintains a record of modifications to the master table 

      in a snapshot. It is stored in the same database as master table and is 

      only available for simple snapshots. It should be created before creating 

      snapshots.

      70. When will the data in the snapshot log be used ?

      The data in the snapshot log is used during fast references of the table's 

      snapshots.

      71. What are the pre-requisites to create a snapshot log ?

      We must be able to create a after row trigger on table (i.e. it should not 

      be already available)

      After giving table previleges.

      We cannot specify snapshot log name because oracle uses the name of the 

      master table in the name of the database objects that support its snapshot 

      log.

      The master table name should be less than or equal to 23 characters.

      (The table name created will be MLOG$_tablename, and trigger name will be 

      TLOG$_tablename)

      72. What are the benefits of distributed options in databases ?

      Database on other servers can be updated and those transactions can be 

      grouped together with others in a logical unit.

      Database uses a two phase commit

      73. What is a two-phase commit ?

      Database on other servers can be updated and those transactions can be 

      grouped together with others in a logical unit is called two-phase commit. 

      They are

      The Preparation Phase : An initiating node called the global coordinator 

      notifies all sites involved in the transaction to be ready either commit 

      or rollback the transaction.

      The Commit Phase : If there is no problem with prepare phase, then all 

      sites commit their transactions. If a network or node failure occurs, then 

      all sites rollback their transactions.

      3.6 Managing Backup & Recovery

      74. What are the different methods of backing up oracle database ?

      Logical Backups

      Cold Backups

      Hot Backups (Archive log)

      75. What is a logical 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.

      76. What is cold backup ? What are the elements of it ?

      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

      Then init.ora file (optional)

      77. What are the different kind of export backups ?

      Full backup - Complete database

      Incremental Backup - Only affected tables from last incremental date / 

      Full backup date

      Cumulative backup - Only affected table from the last cumulative date / 

      Full backup date

      78. What is hot backup and how it can be taken ?

      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

      On control file.

      79. What is the use of FILE option in EXP command ?

      To give the export file name.

      80. What is the use of COMPRESS option in EXP command ?

      Flag to indicate whether export should compress fragmented segments into 

      single extents.

      81. What is the use of GRANT option in EXP command ?

      A flag to indicate whether grants on database objects will be exported or 

      not. Values is 'Y' or 'N'.

      82. What is the use of INDEXES option in EXP command ?

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

      83. What is use of ROWS option in EXP command ?

      Flag to indicate whether table rows should be exported. If 'N' only DDL 

      statements for the database objects will be created.

      84. What is the use of CONSTRAINTS option in EXP command ?

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

      85. What is the use of FULL option in EXP command ?

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

      86. What is the use of OWNER option in EXP command ?

      List of table accounts should be exported.

      87. What is the use of TABLES option in EXP command ?

      List of tables should be exported.

      88. What is use of RECORD LENGTH option in EXP command ?

      Record length in bytes.

      89. What is use of INCTYPE option in EXP command ?

      Type export should be performed. COMPLETE, CUMULATIVE, INCREMENTAL

      90. What is use of RECORD option in EXP command ?

      For incremental exports, the flag indicates whether a record will be 

      stored in data dictionary tables recording the export.

      91. What is the use of PARFILE option in EXP command ?

      Name of the parameter file to passed for export.

      92. What is the use of ANALYSE (Ver 7) option in EXP command ?

      A flag to indicate whether statistical information about the exported 

      objects should be written to export dump file.

      93. What is use of CONSISTENT (Ver 7) option in EXP command ?

      A flag to indicate whether a read consistent version of all the exported 

      objects should be maintained.

      94. What is the use of Log (Ver 7) option in EXP command ?

      The name of file to which log of the export will be written.

      95. What is use of FILE option in IMP command ?

      The name of file from which import should be performed.

      96. What is the use of SHOW option in IMP command ?

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

      97. What is the use of IGNORE option in IMP command ?

      A flag to indicate whether import should ignore errors encounter when 

      issuing CREATE command.

      98. What is the use of GRANT option in IMP command ?

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

      99. What is use of INDEXES option in IMP command ?

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

      100. What is use of ROWS option in IMP command ?

      A flag to indicate whether rows should be imported. I f this is set to 'N' 

      then only DDL for the database objects will be executed ?

      101. What is the use of FULL option in IMP command ?

      A flag to indicate whether full import should be done or not.

      102. What is the use of FROMUSER option in IMP command ?

      A list of database accounts whose objects should be read from the export 

      dump file.

      103. What is use of TOUSER option in IMP command ?

      A list of database accounts into which objects in the export dump file 

      will be imported

      104. What is use of TABLES option in IMP command ?

      A list of tables to be imported.

      105. What is use of RECORDLENGTH option in IMP command ?

      The length of the record in bytes of the export dump file.

      106. What is use of INCTYPE option in the IMP command ?

      The type of import being performed.

      107. What is use of COMMIT option in IMP command ?

      A flag to indicate whether import should commit after each array. If 'N' 

      then commit will take place at table level

      108. What is use of PARFILE option in IMP command ?

      Name of the parameter file to passed for import command.

      109. What is use of INDEXFILE option in IMP command ?

      If filename is given then all the DDL will be created in the given file.

      110. What is use of DESTROY (Ver 7) option in IMP command ?

      A flag to indicate whether the create tablespace command found in dump 

      files from full exports will be executed.

      111. What is use of LOG option in IMP command ?

      Name of the file to which the log of the import will be written.

      112. Consider a case below : User is taking the backup in the following 

      fashion :

      Type F I I I I C I I I I C I I

      Date 1 2 3 4 5 6 7 8 9 10 11 12 13

      F - Full Backup

      I - Incremental Backup

      C - Cumulative Backup

      Suppose database crash on 14th morning. How can we retrieve the database ?

      Create the database

      Import from the Full backup which was taken on 1st

      Import from Cumulative backups which was taken on 6th

      Import from Cumulative backups which was taken on 1th

      Import from the Incremental backups 12,13 respectively.

      Now the database will be available to latest status provided there is no 

      transaction taken place after the 13th incremental backup.

      113. List the steps to restore the database if data file lost. (Assume  

we are taking hot backups)

      Copy the lost file from the backup to the original location

      Start the instance

      Mount the database

      Recover the database using recover database command

      Open the database

      114. What are the points to be taken care when we are using SQL*Loader for 

      importing data from flat files ?

      Whether table and indexes are properly sized.

      Direct option being used or not (Ver 7)

      If one time load do not create any index until data has been loaded and 

      table size is verified.

      115. What are the advantages of using direct path option in SQL*Loader ?

      It bypasses the normal processing of insert statements and instead writes 

      directly to tables data blocks.

      When direct option is used index become invalid and once the load complete 

      the new key is merged with all old one and bring the status to valid.

      Data should be presorted otherwise it needs the double the size in 

      tablespace.

      116. What are areas a DBA can monitor the database using SQLDBA command?

      DBA can monitor the following areas to do fine tuning of the database :

      Processes

      Sessions

      Tables(Locks etc)

      SQL Area

      Library Cache

      Latch

      Locks

      File I/O

      System I/O

      Rollback Segments

      Statistics (System, Sessions)

      Apart from this all DBA activities can be performed through SQLDBA 

command.

      DDE ¡V OLE

      DDE - Dynamic Data Exchange.

      DLL - Dynamic Link Library

      OLE - Object Linking and Embedding.

      MAPI ¡V Messaging Application Program Interface