Rapid pagination without using OFFSET
- PHP:
>=5.6
- j4mie/idiorm:
^5.4
, j4mie/paris:^1.5
- lampager/lampager:
^0.4
composer require lampager/lampager-idiorm
You can wrap ORM
instance with global function lampager()
to make it chainable.
$cursor = [
'id' => 3,
'created_at' => '2017-01-10 00:00:00',
'updated_at' => '2017-01-20 00:00:00',
];
$result = lampager(ORM::for_table('posts')->where_equal('user_id', 1))
->forward()
->limit(5)
->order_by_desc('updated_at') // ORDER BY `updated_at` DESC, `created_at` DESC, `id` DESC
->order_by_desc('created_at')
->order_by_desc('id')
->seekable()
->paginate($cursor)
->to_json(JSON_PRETTY_PRINT);
It will run the optimized query.
SELECT * FROM (
SELECT * FROM `posts`
WHERE `user_id` = 1
AND (
`updated_at` = '2017-01-20 00:00:00' AND `created_at` = '2017-01-10 00:00:00' AND `id` > 3
OR
`updated_at` = '2017-01-20 00:00:00' AND `created_at` > '2017-01-10 00:00:00'
OR
`updated_at` > '2017-01-20 00:00:00'
)
ORDER BY `updated_at` ASC, `created_at` ASC, `id` ASC
LIMIT 1
) `temporary_table`
UNION ALL
SELECT * FROM (
SELECT * FROM `posts`
WHERE `user_id` = 1
AND (
`updated_at` = '2017-01-20 00:00:00' AND `created_at` = '2017-01-10 00:00:00' AND `id` <= 3
OR
`updated_at` = '2017-01-20 00:00:00' AND `created_at` < '2017-01-10 00:00:00'
OR
`updated_at` < '2017-01-20 00:00:00'
)
ORDER BY `updated_at` DESC, `created_at` DESC, `id` DESC
LIMIT 6
) `temporary_table`
And you'll get
{
"records": [
{
"id": 3,
"user_id": 1,
"text": "foo",
"created_at": "2017-01-10 00:00:00",
"updated_at": "2017-01-20 00:00:00"
},
{
"id": 5,
"user_id": 1,
"text": "bar",
"created_at": "2017-01-05 00:00:00",
"updated_at": "2017-01-20 00:00:00"
},
{
"id": 4,
"user_id": 1,
"text": "baz",
"created_at": "2017-01-05 00:00:00",
"updated_at": "2017-01-20 00:00:00"
},
{
"id": 2,
"user_id": 1,
"text": "qux",
"created_at": "2017-01-17 00:00:00",
"updated_at": "2017-01-18 00:00:00"
},
{
"id": 1,
"user_id": 1,
"text": "quux",
"created_at": "2017-01-16 00:00:00",
"updated_at": "2017-01-18 00:00:00"
}
],
"has_previous": false,
"previous_cursor": null,
"has_next": true,
"next_cursor": {
"updated_at": "2017-01-18 00:00:00",
"created_at": "2017-01-14 00:00:00",
"id": 6
}
}
Question: How about Tuple Comparison?
With this feature, SQL statements should be simpler. However, according to SQL Feature Comparison, some RDBMS, such as SQLServer, do not support this syntax. Therefore, Lampager continuously uses redundant statements.
Note: See also lampager/lampager.
Name | Type | Parent Class | Description |
---|---|---|---|
Lampager\Idiorm\Paginator |
Class | Lampager\Paginator |
Fluent factory implementation for Idiorm and Paris |
Lampager\Idiorm\Processor |
Class | Lampager\AbstractProcessor |
Processor implementation for Idiorm and Paris |
Lampager\Idiorm\PaginationResult |
Class | Lampager\PaginationResult |
PaginationResult implementation for Idiorm and Paris |
- All camelCase methods in
Paginator
,Processor
andPaginationResult
can be invoked by snake_case style.
Note: See also lampager/lampager.
Create a new paginator instance.
If you use global function lampager()
, however, you don't need to directly instantiate.
static Paginator create(\ORM|\ORMWrapper $builder): static
Paginator::__construct(\ORM|\ORMWrapper $builder)
Transform Lampager Query into Illuminate builder.
Paginator::transform(\Lampager\Query $query): \ORM|\ORMWrapper
Perform configure + transform.
Paginator::build(\Lampager\Contracts\Cursor|array $cursor = []): \ORM|\ORMWrapper
Perform configure + transform + process.
Paginator::paginate(\Lampager\Contracts\Cursor|array $cursor = []): \Lampager\idiorm\PaginationResult
(mixed)
$cursor
An associative array that contains$column => $value
or an object that implements\Lampager\Contracts\Cursor
. It must be all-or-nothing.- For initial page, omit this parameter or pass empty array.
- For subsequent pages, pass all parameters. Partial parameters are not allowd.
e.g.
object(Lampager\Idiorm\PaginationResult)#1 (5) {
["records"]=>
array(5) {
[0]=>
object(ORM)#2 (22) { ... }
[1]=>
object(ORM)#3 (22) { ... }
[2]=>
object(ORM)#4 (22) { ... }
[3]=>
object(ORM)#5 (22) { ... }
[4]=>
object(ORM)#6 (22) { ... }
}
["hasPrevious"]=>
bool(false)
["previousCursor"]=>
NULL
["hasNext"]=>
bool(true)
["nextCursor"]=>
array(2) {
["updated_at"]=>
string(19) "2017-01-18 00:00:00"
["created_at"]=>
string(19) "2017-01-14 00:00:00"
["id"]=>
int(6)
}
}
Invoke Processor methods.
Paginator::useFormatter(\Lampager\Formatter|callable $formatter): $this
Paginator::restoreFormatter(): $this
Paginator::process(\Lampager\Query $query, array|\IdiormResultSet $rows): \Lampager\idiorm\PaginationResult
Convert the object into array.
IMPORTANT: camelCase properties are converted into snake_case form.
PaginationResult::toArray(): array
PaginationResult::jsonSerialize(): array
Call IdiormResultSet
methods.
PaginationResult::__call(string $name, array $args): mixed