<?php
namespace Illuminate\Database\Concerns;
use Illuminate\Container\Container;
use Illuminate\Pagination\LengthAwarePaginator;
use Illuminate\Pagination\Paginator;
trait BuildsQueries
{
/**
* Chunk the results of the query.
*
* @param int $count
* @param callable $callback
* @return bool
*/
public function chunk($count, callable $callback)
{
$this->enforceOrderBy();
$page = 1;
do {
// We'll execute the query for the given page and get the results. If there are
// no results we can just break and return from here. When there are results
// we will call the callback with the current chunk of these results here.
$results = $this->forPage($page, $count)->get();
$countResults = $results->count();
if ($countResults == 0) {
break;
}
// On each chunk result set, we will pass them to the callback and then let the
// developer take care of everything within the callback, which allows us to
// keep the memory low for spinning through large result sets for working.
if ($callback($results, $page) === false) {
return false;
}
unset($results);
$page++;
} while ($countResults == $count);
return true;
}
/**
* Execute a callback over each item while chunking.
*
* @param callable $callback
* @param int $count
* @return bool
*/
public function each(callable $callback, $count = 1000)
{
return $this->chunk($count, function ($results) use ($callback) {
foreach ($results as $key => $value) {
if ($callback($value, $key) === false) {
return false;
}
}
});
}
/**
* Chunk the results of a query by comparing IDs.
*
* @param int $count
* @param callable $callback
* @param string|null $column
* @param string|null $alias
* @return bool
*/
public function chunkById($count, callable $callback, $column = null, $alias = null)
{
$column = $column ?? $this->defaultKeyName();
$alias = $alias ?? $column;
$lastId = null;
do {
$clone = clone $this;
// We'll execute the query for the given page and get the results. If there are
// no results we can just break and return from here. When there are results
// we will call the callback with the current chunk of these results here.
$results = $clone->forPageAfterId($count, $lastId, $column)->get();
$countResults = $results->count();
if ($countResults == 0) {
break;
}
// On each chunk result set, we will pass them to the callback and then let the
// developer take care of everything within the callback, which allows us to
// keep the memory low for spinning through large result sets for working.
if ($callback($results) === false) {
return false;
}
$lastId = $results->last()->{$alias};
unset($results);
} while ($countResults == $count);
return true;
}
/**
* Execute a callback over each item while chunking by id.
*
* @param callable $callback
* @param int $count
* @param string $column
* @param string $alias
* @return bool
*/
public function eachById(callable $callback, $count = 1000, $column = null, $alias = null)
{
return $this->chunkById($count, function ($results) use ($callback) {
foreach ($results as $key => $value) {
if ($callback($value, $key) === false) {
return false;
}
}
}, $column, $alias);
}
/**
* Execute the query and get the first result.
*
* @param array|string $columns
* @return \Illuminate\Database\Eloquent\Model|object|static|null
*/
public function first($columns = ['*'])
{
return $this->take(1)->get($columns)->first();
}
/**
* Apply the callback's query changes if the given "value" is true.
*
* @param mixed $value
* @param callable $callback
* @param callable|null $default
* @return mixed|$this
*/
public function when($value, $callback, $default = null)
{
if ($value) {
return $callback($this, $value) ?: $this;
} elseif ($default) {
return $default($this, $value) ?: $this;
}
return $this;
}
/**
* Pass the query to a given callback.
*
* @param callable $callback
* @return \Illuminate\Database\Query\Builder
*/
public function tap($callback)
{
return $this->when(true, $callback);
}
/**
* Apply the callback's query changes if the given "value" is false.
*
* @param mixed $value
* @param callable $callback
* @param callable|null $default
* @return mixed|$this
*/
public function unless($value, $callback, $default = null)
{
if (! $value) {
return $callback($this, $value) ?: $this;
} elseif ($default) {
return $default($this, $value) ?: $this;
}
return $this;
}
/**
* Create a new length-aware paginator instance.
*
* @param \Illuminate\Support\Collection $items
* @param int $total
* @param int $perPage
* @param int $currentPage
* @param array $options
* @return \Illuminate\Pagination\LengthAwarePaginator
*/
protected function paginator($items, $total, $perPage, $currentPage, $options)
{
return Container::getInstance()->makeWith(LengthAwarePaginator::class, compact(
'items', 'total', 'perPage', 'currentPage', 'options'
));
}
/**
* Create a new simple paginator instance.
*
* @param \Illuminate\Support\Collection $items
* @param int $perPage
* @param int $currentPage
* @param array $options
* @return \Illuminate\Pagination\Paginator
*/
protected function simplePaginator($items, $perPage, $currentPage, $options)
{
return Container::getInstance()->makeWith(Paginator::class, compact(
'items', 'perPage', 'currentPage', 'options'
));
}
}