SQL::Statement::Operation (3pm)

  # 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 );

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

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

new

Instantiates new operation term.

value

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

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).

\s-1DESTROY\s0

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

# 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 );

SQL::Statement::Operation::Neg

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

operate

Return the logical negated value of the left operand.

# 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 );

SQL::Statement::Operation::And implements the logical \*(C`and\*(C' operation between two terms.

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

operate

Return the result of the logical \*(C`and\*(C' operation for the values of the left and right operand.

# 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 );

SQL::Statement::Operation::Or implements the logical \*(C`or\*(C' operation between two terms.

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

operate

Return the result of the logical \*(C`or\*(C' operation for the values of the left and right operand.

# 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 );

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

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

operate

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

# 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 );

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

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

operate

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

# 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 );

SQL::Statement::Operation::Contains expects the right operand is an array of SQL::Statement::Term 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}

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

operate

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

# 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 );

SQL::Statement::Operation::Between expects the right operand is an array of 2 SQL::Statement::Term 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) )

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

operate

Returns true when the left term is between both right terms

# 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 );

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.

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

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.

# 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 );

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

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

numcmp

Return true when \*(C`$left == $right\*(C'

strcmp

Return true when \*(C`$left eq $right\*(C'

# 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 );

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

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

numcmp

Return true when \*(C`$left != $right\*(C'

strcmp

Return true when \*(C`$left ne $right\*(C'

# 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 );

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

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

numcmp

Return true when \*(C`$left < $right\*(C'

strcmp

Return true when \*(C`$left lt $right\*(C'

# 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 );

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

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

numcmp

Return true when $left $right>

strcmp

Return true when \*(C`$left gt $right\*(C'

# 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 );

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

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

numcmp

Return true when \*(C`$left <= $right\*(C'

strcmp

Return true when \*(C`$left le $right\*(C'

# 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 );

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

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

numcmp

Return true when $left = $right>

strcmp

Return true when \*(C`$left ge $right\*(C'

# 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 );

SQL::Statement::Operation::Regexp implements the comparisons for the \*(C`LIKE\*(C' operation family.

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

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 \*(C`a LIKE b\*(C' in not supported.

regexp

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

# 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 );

SQL::Statement::Operation::Like is used to to the comparisons for the \*(C`LIKE\*(C' operation.

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

regexp

Returns \*(C`qr/^$right$/s\*(C'

# 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 );

SQL::Statement::Operation::Clike is used to to the comparisons for the \*(C`CLIKE\*(C' operation.

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

regexp

Returns \*(C`qr/^$right$/si\*(C'

# 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 );

SQL::Statement::Operation::RLike is used to to the comparisons for the \*(C`RLIKE\*(C' operation.

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

regexp

Returns \*(C`qr/$right$/s\*(C'

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

All rights reserved.

You may distribute this module under the terms of either the \s-1GNU\s0 General Public License or the Artistic License, as specified in the Perl \s-1README\s0 file.