/ 
DBIx-QuickORM-0.000028
⭐ Starred 0 / DBIx::QuickORM::Handle::Column

NAME

DBIx::QuickORM::Handle::Column - Aggregate and single-column reads for a handle.

DESCRIPTION

A thin wrapper binding a DBIx::QuickORM::Handle to one column (or column expression) so you can read aggregates over it (sum/min/max/avg/ count/func) or pull the column's values directly (all/iterator).

Obtain one from a handle:

my $col = $con->handle('orders')->where({paid => 1})->column('total');

Every fetch runs a single SELECT that reuses the handle's where (and any group_by/having), returns the raw database scalar (no type inflation, like count()), and never enters the identity map.

SYNOPSIS

my $orders = $con->handle('orders');

my $total   = $orders->column('total')->sum;
my $biggest = $orders->column('total')->max;
my $joined  = $orders->column('sku')->func('GROUP_CONCAT');

# Literal expression (emitted verbatim):
my $revenue = $orders->column(\'price * qty')->sum;

# Per-group values line up with a grouped handle:
my @totals = $orders->group_by('category')->column('total')->all;

ATTRIBUTES

handle

The DBIx::QuickORM::Handle this column reads through.

column

The column: a plain string name, or a scalar reference holding literal SQL.

PUBLIC METHODS

$val = $col->sum
$val = $col->min
$val = $col->max
$val = $col->avg
$val = $col->count

Run the matching SQL aggregate over the column and return the scalar result (undef when there are no rows).

$val = $col->func($name)

Run an arbitrary single-argument aggregate $name over the column (e.g. $col->func('GROUP_CONCAT')). The function name must be a bare identifier (word characters only).

@vals = $col->all

The column's value from every row, as a list of plain scalars.

$iter = $col->iterator

An iterator yielding the column's value one row at a time.

PRIVATE METHODS

$val = $col->_aggregate($func)

Apply an aggregate function to the column expression and fetch the scalar.

$sql = $col->_column_sql

The column rendered as SQL: a quoted identifier for a plain name, or the literal SQL verbatim for a scalar reference.

SOURCE

The source code repository for DBIx::QuickORM can be found at https://github.com/exodist/DBIx-QuickORM.

MAINTAINERS

Chad Granum <exodist7@gmail.com>

AUTHORS

Chad Granum <exodist7@gmail.com>

COPYRIGHT

Copyright Chad Granum <exodist7@gmail.com>.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See https://dev.perl.org/licenses/