slide1 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Oracle9 i Developer: PL/SQL Programming PowerPoint Presentation
Download Presentation
Oracle9 i Developer: PL/SQL Programming

Loading in 2 Seconds...

play fullscreen
1 / 16

Oracle9 i Developer: PL/SQL Programming - PowerPoint PPT Presentation

  • Uploaded on

Oracle9 i Developer: PL/SQL Programming. Chapter 7. Program Unit Dependencies. Objectives. Identify local program unit dependencies Determine direct and indirect dependencies View data dictionary information concerning dependencies Run the dependency tree utility

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Oracle9 i Developer: PL/SQL Programming' - manasa

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Oracle9i Developer:

PL/SQL Programming

Chapter 7

Program Unit


  • Identify local program unit dependencies
  • Determine direct and indirect dependencies
  • View data dictionary information concerning dependencies
  • Run the dependency tree utility
  • Identify the unique nature of package dependencies
  • Understand remote object dependency actions
  • Use remote dependency invalidation methods
  • Avoid recompilation errors
  • Grant program unit privileges
program unit dependencie s
Program Unit Dependencies
  • Relationships or dependencies determine the validity of any program unit after modifications to database objects that the program unit references
  • This validity determines the need for recompilation
  • A procedure calls a function: the procedure is a dependent object and the function is the referenced object
brewbean s challenge
Brewbean’s Challenge
  • Need to take any steps possible to make the execution more efficient
  • Users have been hitting some unexpected errors related to recent modifications to the database and program units
  • In this light, need to review database dependencies and their impact
local dependency activity
Local Dependency Activity
  • Status of program unit can be checked using USER_OBJECTS
  • When a referenced object is modified the status of the dependent object changes to INVALID
  • INVALID status indicates need for recompilation
  • ALTER COMPILE command used to recompile a program unit
automatic recompilation
Automatic Recompilation
  • Upon execution of a program unit with an INVALID status, the system will automatically recompile
  • Drawbacks:
    • Recompilation of dependent objects tests the changes to the referenced objects which could raise errors at runtime
    • Recompilation processing occurs during runtime
direct indirect dependencies
Direct & Indirect Dependencies
  • Direct – a procedure calls a function
  • Indirect – a procedure calls a procedure which calls a function: the dependency between the first procedure and the function is indirect
  • Indirect dependencies have same affect as direct dependencies
data dictionary
Data Dictionary
  • USER_DEPENDENCIES identify direct dependencies
  • Use WHERE clause on name column to analyze a particular object
  • DBA_DEPENDENCIES will identify direct dependencies of objects in all schemas
dependency tree utility
Dependency Tree Utility
  • Mechanism to map direct and indirect dependencies
  • Execute utldtree.sql script once to set up the feature
  • Deptree_fill procedure used to analyze an object
  • Two views:
    • Deptree: numeric scheme
    • Ideptree: indented scheme
package dependencies
Package Dependencies
  • Modifications to package specification will change status of dependent objects
  • Modifications to package body only does NOT change status of dependent objects
  • Separation of code in packages:
    • Minimizes recompilation needs
    • Dependent objects to be developed prior to the package body being created
remote object dependencies
Remote Object Dependencies
  • Database links are used to connect to other Oracle databases
  • Links allow calls to objects in other databases - these objects are called remote objects
  • When remote objects are modified, local dependent objects are not initially flagged as INVALID
  • Remote dependencies are not checked until runtime
remote invalidation methods
Remote Invalidation Methods
  • Timestamp: compares the last date of modification of dependent and referenced objects
  • Signature: compares the parameter modes, data types, and order
  • Timestamp is the default method
  • Databases in different time zones generate unnecessary recompilation using the timestamp method
avoiding recompilation errors
Avoiding Recompilation Errors
  • Use %TYPE and %ROWTYPE attributes
  • Use the ‘*’ notation in queries to select all columns
  • Use a column list in INSERT statements
program unit privileges

System Privilege



Allows a user to create, modify, and drop program units within their own schema.


Allows a user to create program units in any schema. Does not allow the modification or dropping of the program units.


Allows a user to modify program units in any schema.


Allows a user to drop program units in any schema.

EXECUTE ON program_unit_name

Allows a user to execute a specific program unit.


Allows a user to execute program units in any schema.

Program Unit Privileges
privileges data dictionary

View Name



Shows all privileges of the current schema, direct and indirect


Shows all roles granted to the current schema


Shows only direct privileges of the current schema


Shows only direct roles granted to the current schema

Privileges - Data Dictionary
  • Program unit status changes when referenced object is modified
  • INVALID status indicates a need for recompilation
  • Direct and indirect dependencies both affect status
  • Dependency tree utility allows mapping of both direct and indirect dependencies
  • Packages minimize recompilation needs
  • Remote dependencies do not update status until runtime
  • Appropriate privileges needed to create and use program units