SQL::Statement::Operation - base class for all operation terms



NAME

SQL::Statement::Operation - base class for all operation terms


SYNOPSIS

  # create an operation with an SQL::Statement object as owner, specifying
  # the operation name (for error purposes), the left and the right
  # operand
  my $term = SQL::Statement::Operation->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation is an abstract base class providing the interface for all operation terms.


INHERITANCE

  SQL::Statement::Operation
  ISA SQL::Statement::Term


METHODS

new

Instantiates new operation term.

value

Return the result of the operation of the term by calling the operate manpage

operate

Abstract method which will do the operation of the term. Must be overridden by derived classes.

op

Returns the name of the executed operation.

left

Returns the left operand (if any).

right

Returns the right operand (if any).

DESTROY

Destroys the term and undefines the weak reference to the owner as well as the stored operation, the left and the right operand.


NAME

SQL::Statement::Operation::Neg - negate operation


SYNOPSIS

  # create an <not> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and B<no> right operand
  my $term = SQL::Statement::Neg->new( $owner, $op, $left, undef );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Neg


INHERITANCE

  SQL::Statement::Operation::Neg
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Return the logical negated value of the left operand.


NAME

SQL::Statement::Operation::And - and operation


SYNOPSIS

  # create an C<and> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::And->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::And implements the logical and operation between two terms.


INHERITANCE

  SQL::Statement::Operation::And
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Return the result of the logical and operation for the the value manpages of the left and right operand.


NAME

SQL::Statement::Operation::Or - or operation


SYNOPSIS

  # create an C<or> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Or->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Or implements the logical or operation between two terms.


INHERITANCE

  SQL::Statement::Operation::Or
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Return the result of the logical or operation for the the value manpages of the left and right operand.


NAME

SQL::Statement::Operation::Is - is operation


SYNOPSIS

  # create an C<is> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Is->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Is supports: IS NULL, IS TRUE and IS FALSE. The right operand is always evaluated in boolean context in case of IS TRUE and IS FALSE. IS NULL returns true even if the left term is an empty string ('').


INHERITANCE

  SQL::Statement::Operation::Is
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Returns true when the left term is null, true or false - based on the requested right value.


NAME

SQL::Statement::Operation::ANSI::Is - is operation


SYNOPSIS

  # create an C<is> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Is->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::ANSI::Is supports: IS NULL, IS TRUE and IS FALSE. The right operand is always evaluated in boolean context in case of IS TRUE and IS FALSE. IS NULL returns true if the right term is not defined, false otherwise.


INHERITANCE

  SQL::Statement::Operation::Is
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Returns true when the left term is null, true or false - based on the requested right value.


NAME

SQL::Statement::Operation::Contains - in operation


SYNOPSIS

  # create an C<in> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Contains->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Contains expects the right operand is an array of the SQL::Statement::Term manpage instances. It checks whether the left operand is in the list of the right operands or not like:

  $left->value($eval) ~~ map { $_->value($eval) } @{$right}


INHERITANCE

  SQL::Statement::Operation::Contains
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Returns true when the left term is equal to any of the right terms


NAME

SQL::Statement::Operation::Between - between operation


SYNOPSIS

  # create an C<between> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Between->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Between expects the right operand is an array of 2 the SQL::Statement::Term manpage instances. It checks whether the left operand is between the right operands like:

     ( $left->value($eval) >= $right[0]->value($eval) )
  && ( $left->value($eval) <= $right[1]->value($eval) )


INHERITANCE

  SQL::Statement::Operation::Between
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Returns true when the left term is between both right terms


NAME

SQL::Statement::Operation::Equality - abstract base class for comparisons


SYNOPSIS

  # create an C<equality> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Equality->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Equality implements compare operations between two terms - choosing either numerical comparison or string comparison, depending whether both operands are numeric or not.


INHERITANCE

  SQL::Statement::Operation::Equality
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Return the result of the comparison.

numcmp

Abstract method which will do the numeric comparison of both terms. Must be overridden by derived classes.

strcmp

Abstract method which will do the string comparison of both terms. Must be overridden by derived classes.


NAME

SQL::Statement::Operation::Equal - implements equal operation


SYNOPSIS

  # create an C<equal> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Equal->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Equal implements compare operations between two numbers and two strings.


INHERITANCE

  SQL::Statement::Operation::Equal
  ISA SQL::Statement::Operation::Equality
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

numcmp

Return true when $left == $right

strcmp

Return true when $left eq $right


NAME

SQL::Statement::Operation::NotEqual - implements not equal operation


SYNOPSIS

  # create an C<not equal> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::NotEqual->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::NotEqual implements negated compare operations between two numbers and two strings.


INHERITANCE

  SQL::Statement::Operation::NotEqual
  ISA SQL::Statement::Operation::Equality
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

numcmp

Return true when $left != $right

strcmp

Return true when $left ne $right


NAME

SQL::Statement::Operation::Lower - implements lower than operation


SYNOPSIS

  # create an C<lower than> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Lower->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Lower implements lower than compare operations between two numbers and two strings.


INHERITANCE

  SQL::Statement::Operation::Lower
  ISA SQL::Statement::Operation::Equality
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

numcmp

Return true when $left < $right

strcmp

Return true when $left lt $right


NAME

SQL::Statement::Operation::Greater - implements greater than operation


SYNOPSIS

  # create an C<greater than> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Greater->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Greater implements greater than compare operations between two numbers and two strings.


INHERITANCE

  SQL::Statement::Operation::Greater
  ISA SQL::Statement::Operation::Equality
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

numcmp

Return true when $left $right>

strcmp

Return true when $left gt $right


NAME

SQL::Statement::Operation::LowerEqual - implements lower equal operation


SYNOPSIS

  # create an C<lower equal> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::LowerEqual->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::LowerEqual implements lower equal compare operations between two numbers and two strings.


INHERITANCE

  SQL::Statement::Operation::LowerEqual
  ISA SQL::Statement::Operation::Equality
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

numcmp

Return true when $left <= $right

strcmp

Return true when $left le $right


NAME

SQL::Statement::Operation::GreaterEqual - implements greater equal operation


SYNOPSIS

  # create an C<greater equal> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::GreaterEqual->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::GreaterEqual implements greater equal compare operations between two numbers and two strings.


INHERITANCE

  SQL::Statement::Operation::GreaterEqual
  ISA SQL::Statement::Operation::Equality
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

numcmp

Return true when $left = $right>

strcmp

Return true when $left ge $right


NAME

SQL::Statement::Operation::Regexp - abstract base class for comparisons based on regular expressions


SYNOPSIS

  # create an C<regexp> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Regexp->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Regexp implements the comparisons for the LIKE operation family.


INHERITANCE

  SQL::Statement::Operation::Regexp
  ISA SQL::Statement::Operation
    ISA SQL::Statement::Term


METHODS

operate

Return the result of the comparison.

right

Returns the regular expression based on the right term. The right term is expected to be constant - so a LIKE b in not supported.

regexp

Abstract method which must return a regular expression (qr//) from the given string. Must be overridden by derived classes.


NAME

SQL::Statement::Operation::Like - implements the like operation


SYNOPSIS

  # create an C<like> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Like->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Like is used to to the comparisons for the LIKE operation.


INHERITANCE

  SQL::Statement::Operation::Like
  ISA SQL::Statement::Operation::Regexp
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

regexp

Returns qr/^$right$/s


NAME

SQL::Statement::Operation::Clike - implements the clike operation


SYNOPSIS

  # create an C<clike> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::Clike->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::Clike is used to to the comparisons for the CLIKE operation.


INHERITANCE

  SQL::Statement::Operation::Clike
  ISA SQL::Statement::Operation::Regexp
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

regexp

Returns qr/^$right$/si


NAME

SQL::Statement::Operation::RLike - implements the rlike operation


SYNOPSIS

  # create an C<rlike> operation with an SQL::Statement object as owner,
  # specifying the operation name, the left and the right operand
  my $term = SQL::Statement::RLike->new( $owner, $op, $left, $right );
  # access the result of that operation
  $term->value( $eval );


DESCRIPTION

SQL::Statement::Operation::RLike is used to to the comparisons for the RLIKE operation.


INHERITANCE

  SQL::Statement::Operation::RLike
  ISA SQL::Statement::Operation::Regexp
    ISA SQL::Statement::Operation
      ISA SQL::Statement::Term


METHODS

regexp

Returns qr/$right$/s


AUTHOR AND COPYRIGHT

Copyright (c) 2009,2010 by Jens Rehsack: rehsackATcpan.org

All rights reserved.

You may distribute this module under the terms of either the GNU General Public License or the Artistic License, as specified in the Perl README file.

 SQL::Statement::Operation - base class for all operation terms