Transcript Document
Perl Specialist
Copyright © 2010 Certification Partners, LLC -- All Rights Reserved
Lesson 1:
Introduction to Perl
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Objectives
• Describe the benefits of Perl
• Explain the role of the Perl interpreter
• Identify the characteristics of Perl’s basic
syntax
• Describe the use of the print function
• Create and execute a simple Perl script
• Define scalar variables
• Use scalar variables to manipulate numerical
and string data
• Use expression operators
• Retrieve data from STDIN
Perl Specialist
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Practical Extracting
and Reporting Language
• Why use Perl?
– Innate flexibility
– Simple syntax
– Relaxed compiler instructions
– Free
Perl Specialist
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Getting Started with Perl
• The shebang line
• Creating a simple Perl script
Perl Specialist
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Scalar and Numerical Variables
• Assignment
• Expressions
Perl Specialist
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String Variables
• Second type of scalar variable
• The print function
Perl Specialist
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Retrieving Data from STDIN
• The chomp() function
Perl Specialist
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Summary
Describe the benefits of Perl
Explain the role of the Perl interpreter
Identify the characteristics of Perl’s basic
syntax
Describe the use of the print function
Create and execute a simple Perl script
Define scalar variables
Use scalar variables to manipulate numerical
and string data
Use expression operators
Retrieve data from STDIN
Perl Specialist
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Lesson 2:
Flow Control in Perl
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Objectives
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Evaluate Boolean expressions
Construct an if statement
Discuss else and elsif branches
Construct a while loop
Construct a do {} while loop
Construct a for loop
Use loop labels
Describe the I/O redirection paradigm
Perl Specialist
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Boolean Expressions in Perl
• Numeric Boolean expressions
• String Boolean expressions
• Logical operators
Perl Specialist
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The if Statement
• The else branch
• The elsif branch
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The while Statement
• Second type of control structure
• Defines a block of code that will be executed
repeatedly as long as some Boolean
expression evaluates as true
Perl Specialist
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The do { } while Statement
• Similar to the while loop except that the
condition is not evaluated until the code
block has already been executed once
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The for Statement
• Includes three expressions separated by
semicolons
• Incorporates facilities for initializing a counter
and incrementing it on each turn through the
code block
Perl Specialist
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Loop-Control Commands
• last
• next
• redo
Perl Specialist
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I/O Redirection
• Many Perl scripts use I/O redirection in place
of more complicated file-handling
subroutines
Perl Specialist
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Summary
Evaluate Boolean expressions
Construct an if statement
Discuss else and elsif branches
Construct a while loop
Construct a do {} while loop
Construct a for loop
Use loop labels
Describe the I/O redirection paradigm
Perl Specialist
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Lesson 3:
Regular Expressions in Perl
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Objectives
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Define regular expressions
Perform pattern matching
Define and use metacharacters
Explain character classes
Define quantifiers and assertions
Perform substitution
Use the binding operator
Perl Specialist
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Introduction to
Regular Expressions
• Pattern binding operators
• Escape sequences and metacharacters
Perl Specialist
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Character Classes
• Indicate a list of characters that one element
in a string will match
Perl Specialist
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Pattern Matching and Substitution
• Back references
Perl Specialist
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Summary
Define regular expressions
Perform pattern matching
Define and use metacharacters
Explain character classes
Define quantifiers and assertions
Perform substitution
Use the binding operator
Perl Specialist
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Lesson 4:
Arrays in Perl
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Objectives
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Describe the purpose of arrays
Define arrays using lists
Access array elements
Use the sort function to sort an array
alphabetically
Use a foreach loop to traverse an array
Use the push and pop functions
Use the shift and unshift functions
Use the split and join functions
Perl Specialist
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Introduction to Perl Arrays
• Initializing arrays
• Accessing array elements
Perl Specialist
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The sort Function
• Accepts an array as an argument,
alphabetizes the elements within the array,
and returns the resultant array
Perl Specialist
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The foreach Statement
• A special control structure designed to iterate
through an array or list
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The push and pop Functions
• The push function adds values to the top of a
stack
• The pop function removes values from a stack
Perl Specialist
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The shift and unshift Functions
• The unshift function adds a value to the
front of an array and shifts the rest of the
array by one
• The shift function removes values from an
array
• Using an array as a queue
Perl Specialist
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The split and join Functions
• The split function accepts two arguments,
a regular expression and a string
• The join function accepts a list of values and
combines them into a single string
Perl Specialist
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Summary
Describe the purpose of arrays
Define arrays using lists
Access array elements
Use the sort function to sort an array
alphabetically
Use a foreach loop to traverse an array
Use the push and pop functions
Use the shift and unshift functions
Use the split and join functions
Perl Specialist
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Lesson 5:
Hashes in Perl
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Objectives
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Describe the purpose of hashes
Define hashes using lists
Access hash elements
Use the delete function
Use the keys function
Use the values function
Use the each function
Use the reverse function
Perl Specialist
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Introduction to Perl Hashes
• Hashes are collections of scalar values that
can be accessed individually
• Hash elements are accessed using an
arbitrary scalar value, called a key
• Also known as associative arrays
Perl Specialist
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Adding and Deleting Hash Elements
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The delete function
The keys function
The values function
The each function
The reverse function
Perl Specialist
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Summary
Describe the purpose of hashes
Define hashes using lists
Access hash elements
Use the delete function
Use the keys function
Use the values function
Use the each function
Use the reverse function
Perl Specialist
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Lesson 6:
Subroutines in Perl
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Objectives
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Define and use a subroutine
Call subroutines directly and indirectly
Pass values to a subroutine
Return a value from a subroutine
Explain variable scope
Pass references to a subroutine
Perl Specialist
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Introduction to Perl Subroutines
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Defining subroutines
Calling subroutines
Passing arguments
Returning values
The sort function and subroutines
Perl Specialist
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Variable Scope
• Variables can be created within subroutines
that are private (specific) to just that
subroutine using the my operator
– The my operator takes a scalar, array, or
hash name and instantiates local versions
inside a subroutine
Perl Specialist
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References
• Creating and referencing anonymous arrays
• Creating and referencing anonymous hashes
• Passing references to subroutines
Perl Specialist
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Summary
Define and use a subroutine
Call subroutines directly and indirectly
Pass values to a subroutine
Return a value from a subroutine
Explain variable scope
Pass references to a subroutine
Perl Specialist
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Lesson 7:
File Input and Output
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Objectives
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Define and use filehandles
Obtain a filehandle using the open function
Output data to a file
Close a file using the close function
Open a file for reading
Use the stat and lstat functions to obtain
information about a file
Perl Specialist
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Perl File Input and Output
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What is a filehandle?
The open function
Outputting data to a file
Opening files for reading
Other file-related functions
Determining information about files
The stat and lstat functions
Perl Specialist
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Summary
Define and use filehandles
Obtain a filehandle using the open function
Output data to a file
Close a file using the close function
Open a file for reading
Use the stat and lstat functions to obtain
information about a file
Perl Specialist
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Lesson 8:
Environment Variables
and Command Line Arguments
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Objectives
• Access and use environment variables
• Use command line arguments
• Define options when handling command line
arguments
Perl Specialist
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Environment Variables
• What are environment variables?
– Shells
Perl Specialist
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Command Line Arguments
• Arguments entered at the command line can
be used in Perl programs
Perl Specialist
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Summary
Access and use environment variables
Use command line arguments
Define options when handling command line
arguments
Perl Specialist
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Lesson 9:
Packages and Modules in Perl
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Objectives
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Describe the purpose of packages
Use the package keyword
Use BEGIN and END blocks
Describe the purpose of modules
Create a module to facilitate code reuse
Incorporate a module into your Perl scripts
using the use and require statements
• Use the Exporter module
Perl Specialist
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Using Packages in Perl
• Namespace
• The package keyword
• Package symbol tables
Perl Specialist
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BEGIN and END Blocks
• Special blocks of code defined within a
package
Perl Specialist
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Using Modules in Perl
• Specially designed Perl scripts that package
functionality for reuse by other Perl scripts
Perl Specialist
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The use and require Statements
• The require statement takes a single
argument (the name of the module to
include)
• The use statement adds symbols directly to
the including package’s symbol table
Perl Specialist
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Summary
Describe the purpose of packages
Use the package keyword
Use BEGIN and END blocks
Describe the purpose of modules
Create a module to facilitate code reuse
Incorporate a module into your Perl scripts
using the use and require statements
Use the Exporter module
Perl Specialist
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Lesson 10:
Object-Oriented Perl
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Objectives
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Describe the purpose of objects
Define objects for use in your Perl scripts
Access object data
Define and use object methods
Use inheritance to expand the functionality of
a class
Perl Specialist
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Introduction to Object-Oriented Perl
• Creating objects
• Object data
• Object methods
Perl Specialist
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Inheritance
• @ISA array
• Destructor methods
Perl Specialist
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Summary
Describe the purpose of objects
Define objects for use in your Perl scripts
Access object data
Define and use object methods
Use inheritance to expand the functionality of
a class
Perl Specialist
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Lesson 11:
Database Connectivity and Perl
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Objectives
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Define database programming
Explain the benefits of using a database
Define and use the Database Interface Module (DBI)
Define and use the Database Driver Module (DBD)
Open a database connection
Close a connection to a database
Query a database
Define and use the Structured Query Language (SQL)
Return records from a database
Insert records into a database
Perl Specialist
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Introduction to Database Connectivity
• Database programming
• Database Interface Module
• Database Driver Module
Perl Specialist
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Interacting with Databases
1. Connect to the database
2. Query the database
3. Display the results
4. Close the connection
Perl Specialist
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Connecting to Databases
• The connect method
Perl Specialist
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Structured Query Language
• Data Definition Language
– CREATE
– DROP
• Data Query Language
• Data Manipulation Language
– INSERT
– DELETE
– UPDATE
Perl Specialist
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Quoting Operators
• Perl includes quoting operators that can be
used instead of single or double quotation
marks
Perl Specialist
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Summary
Define database programming
Explain the benefits of using a database
Define and use the Database Interface Module (DBI)
Define and use the Database Driver Module (DBD)
Open a database connection
Close a connection to a database
Query a database
Define and use the Structured Query Language (SQL)
Return records from a database
Insert records into a database
Perl Specialist
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Lesson 12:
Debugging Perl Programs
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Objectives
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Debug Perl programs
Use the –w switch
Use the strict module
Trace the execution of a Perl script
Issue commands to the Perl debugger
Design Perl scripts to minimize bugs
Perl Specialist
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Introduction to Debugging Perl Scripts
• Using the print command
• Using the –w switch
• Using the strict module
Perl Specialist
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The Perl Debugger
• Traps and fixes errors in a Perl script
• An interactive Perl environment wherein the
user is prompted for debugger commands
Perl Specialist
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Writing Bug-Free Perl Code
• Preventing errors
• Common Perl errors
Perl Specialist
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Summary
Debug Perl programs
Use the –w switch
Use the strict module
Trace the execution of a Perl script
Issue commands to the Perl debugger
Design Perl scripts to minimize bugs
Perl Specialist
Copyright © 2010 Certification Partners, LLC -- All Rights Reserved
Perl Specialist
Introduction to Perl
Flow Control in Perl
Regular Expressions in Perl
Arrays in Perl
Hashes in Perl
Subroutines in Perl
File Input and Output
Environment Variables and Command Line Arguments
Packages and Modules in Perl
Object-Oriented Perl
Database Connectivity and Perl
Debugging Perl Programs
Perl Specialist
Copyright © 2010 Certification Partners, LLC -- All Rights Reserved