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DBIx::Class::ResultSetUsermContributed Perl DocDBIx::Class::ResultSetColumn(3)

NAME
	 DBIx::Class::ResultSetColumn -	helpful	methods	for messing
	 with a	single column of the resultset

SYNOPSIS
	 $rs = $schema->resultset('CD')->search({ artist => 'Tool' });
	 $rs_column = $rs->get_column('year');
	 $max_year = $rs_column->max; #returns latest year

DESCRIPTION
       A convenience class used	to perform operations on a specific column of
       a resultset.

METHODS
   new
	 my $obj = DBIx::Class::ResultSetColumn->new($rs, $column);

       Creates a new resultset column object from the resultset	and column
       passed as params. Used internally by "get_column" in
       DBIx::Class::ResultSet.

   as_query
       Arguments: none
       Return Value: \[	$sql, @bind_values ]

       Returns the SQL query and bind vars associated with the invocant.

       This is generally used as the RHS for a subquery.

   next
       Arguments: none
       Return Value: $value

       Returns the next	value of the column in the resultset (or "undef" if
       there is	none).

       Much like "next"	in DBIx::Class::ResultSet but just returning the one
       value.

   all
       Arguments: none
       Return Value: @values

       Returns all values of the column	in the resultset (or "undef" if	there
       are none).

       Much like "all" in DBIx::Class::ResultSet but returns values rather
       than result objects.

   reset
       Arguments: none
       Return Value: $self

       Resets the underlying resultset's cursor, so you	can iterate through
       the elements of the column again.

       Much like "reset" in DBIx::Class::ResultSet.

   first
       Arguments: none
       Return Value: $value

       Resets the underlying resultset and returns the next value of the
       column in the resultset (or "undef" if there is none).

       Much like "first" in DBIx::Class::ResultSet but just returning the one
       value.

   single
       Arguments: none
       Return Value: $value

       Much like "single" in DBIx::Class::ResultSet fetches one	and only one
       column value using the cursor directly. If additional rows are present
       a warning is issued before discarding the cursor.

   min
       Arguments: none
       Return Value: $lowest_value

	 my $first_year	= $year_col->min();

       Wrapper for ->func. Returns the lowest value of the column in the
       resultset (or "undef" if	there are none).

   min_rs
       Arguments: none
       Return Value: $resultset

	 my $rs	= $year_col->min_rs();

       Wrapper for ->func_rs for function MIN().

   max
       Arguments: none
       Return Value: $highest_value

	 my $last_year = $year_col->max();

       Wrapper for ->func. Returns the highest value of	the column in the
       resultset (or "undef" if	there are none).

   max_rs
       Arguments: none
       Return Value: $resultset

	 my $rs	= $year_col->max_rs();

       Wrapper for ->func_rs for function MAX().

   sum
       Arguments: none
       Return Value: $sum_of_values

	 my $total = $prices_col->sum();

       Wrapper for ->func. Returns the sum of all the values in	the column of
       the resultset. Use on varchar-like columns at your own risk.

   sum_rs
       Arguments: none
       Return Value: $resultset

	 my $rs	= $year_col->sum_rs();

       Wrapper for ->func_rs for function SUM().

   func
       Arguments: $function
       Return Value: $function_return_value

	 $rs = $schema->resultset("CD")->search({});
	 $length = $rs->get_column('title')->func('LENGTH');

       Runs a query using the function on the column and returns the value.
       Produces	the following SQL:

	 SELECT	LENGTH(	title )	FROM cd	me

   func_rs
       Arguments: $function
       Return Value: $resultset

       Creates the resultset that "func()" uses	to run its query.

   throw_exception
       See "throw_exception" in	DBIx::Class::Schema for	details.

FURTHER	QUESTIONS?
       Check the list of additional DBIC resources.

COPYRIGHT AND LICENSE
       This module is free software copyright by the DBIx::Class (DBIC)
       authors.	You can	redistribute it	and/or modify it under the same	terms
       as the DBIx::Class library.

perl v5.24.1			  2016-06-20   DBIx::Class::ResultSetColumn(3)

NAME | SYNOPSIS | DESCRIPTION | METHODS | FURTHER QUESTIONS? | COPYRIGHT AND LICENSE

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