Who is a DBA?

A Database Administrator (DBA) is a technical person who is responsible for the environmental aspects of a database. In general, these include the following database aspects:

  • Recoverability
  • Integrity
  • Security
  • Availibilty
  • Performance
  • Development and testing support

In other words, a DBA is a person who is responsible for designing, developing and implementing programs, as required, to support the technical capabilities in a database environment.

Pass the following certifications using uCertify PrepKits:

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Configuring Recovery Manager

  • The control file, target database catalog, and Recovery catalog is used to store the RMAN’s persistent settings.
  • The alert log file is used to find out the values of the changed parameters at the time of instance startup.
  • The NLS_LANG parameter must be set to specify the language, territory, and character set used in an application.
  • CONFIGURE RETENTION POLICY CLEAR is a command that will configure the retention policy to the default of REDUNDANCY 1.
  • CONFIGURE is an RMAN command that configures an RMAN environment.
  • The rman target/ command is used to maintain backup copies by connecting to the target database and returns the RMAN prompt to issue further backup commands.
  • The redo files are opened after executing the ALTER DATABASE OPEN command on a database when it is in MOUNT mode.

Understanding Globalization Support
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Retrieving data using the SQL SELECT statement and using single row functions to customize the output

  • /*…*/ and — are used to put comments in an Oracle program.
  • The CREATE TABLE does not end immediately with a semicolon, and a column name cannot start with a numeric value. However, a numeric value can be used in between a column name.
  • Name of a table cannot start with @ special character.
  • Knowing about the GROUP BY clause.

Using sub queries and set operators to solve queries, as well as DDL statements to create and manage tables

  • + (unary), – (unary), *, /, ||, =, !=, <, >, <=, >=, IS NULL, LIKE, BETWEEN, IN, NOT, AND, OR is the correct order of operators precedence.
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General high availability technologies in 10g

  • The ORDER BY clause sorts the records in ascending order and it comes last in the SELECT statement.
  • The Online redo log files and the operating system flat file are used to store a copy of a data dictionary.
  • RMAN can be used to take an incremental backup for tablespaces and data files.
  • The rman target/ command is used to maintain backup copies by connecting to the target database and returns the RMAN prompt to issue further backup commands.
  • The NLS_LANG parameter must be set to specify the language, territory, and character set used in an application.
  • CONFIGURE is an RMAN command that configures an RMAN environment.
  • CONFIGURE RETENTION POLICY CLEAR is a command that will configure the retention policy to the default of REDUNDANCY 1.
  • RMAN is used to migrate the database files from conventional file system storage to ASM storage.
  • The control file, target database catalog, and Recovery catalog are used to store the RMAN’s persistent settings.
  • The redo files are opened after executing the ALTER DATABASE OPEN command on a database when it is in MOUNT mode.
  • RMAN can be used to move database objects from a non-ASM disk location to an ASM disk group.
  • The V dynamic performance view includes the status, the location where the block change tracking file is stored, and the size in bytes of the file.
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Oracle architecture

  • The size of the shared pool can be changed dynamically. The data dictionary cache of the shared pool holds the most recently accessed data dictionary information. The shared pool consists of a library cache and data dictionary cache.
  • Control file, redo log file, and data file are part of an Oracle database.
  • An SGA and Oracle background processes constitute an Oracle instance. An SGA is ended when an Oracle instance is shut down. Multiple users can share data in an SGA.
  • While making modifications in SPFILE, the instance should be in open and running state, whereas in the case of PFILE, the instance will have to be first shut down and restarted before making any modifications in it.
  • V is a dynamic performance view that is used to display the names and the location of all the control files.
  • Following is the correct sequence of the processes that occur when a database is opened:
    1. An initialization parameter file is read.
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New Features of Oracle 10g, Oracle 10g Installation, Server Configuration, and Maintenance of the Software

  • Memory – 512MB, Temp space – 400MB of free space in the /tmp directory applicable for the Unix operating system, Swap space – 1GB or twice the amount of RAM, Free disk space – 1.5GB are the minimum hardware requirements to install Oracle 10g.
  • The Installation Type list box is used to decide the type of installation.
  • Oracle Management Agent (OMA) is a centralized administrative tool that is capable of administering the database server and an application server.
  • The location (/u01/app/oracle) will be considered as the base of Optimal Flexible Architecture (OFA).
  • The password file is used to authenticate the administrative tasks from remote locations.
  • An Oracle 10g client can be used to connect to an Oracle 8i or 9i database by using the following syntax:
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Working with the Photoshop UI

  • Photoshop enables you to save the positions of all the open palettes as a workspace.
  • To load a preserved workspace, choose Window > Workspace, and select the workspace from the submenu.
  • Photoshop lets a user to save the current set of keyboard shortcuts as a workspace.
  • The Slide Show view option (View > Slide Show) of the Bridge displays a group of images one by one at full screen.
  • The As Details view option (View > As Details) of the Bridge displays a list of thumbnails along with the information about each file in the main viewing area of the Bridge workspace.
  • The As Filmstrip view option (View > As Filmstrip) of the Bridge displays thumbnails of files in a scrolling list along with a big preview of the file selected in the list in the main viewing area of the Bridge workspace.
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