I am using rails 3.2. I am paginating my results using .page(1).per_page(10)
like
#users = User.method().page(1).per_page(10)
Now how to find the total count of the users from the pagination
As because #users.count gives 10 from the first page and not the total count
How to get the total count of the users even after pagination
EDIT : #users.total_count gives the whole paginated count
As mentioned in the question, you can get the total count of the records with
#users.total_count
I've added this as an answer for the sake of completeness.
You can use #users.total_count.
However, if you're trying to get the total count for each page, i.e. something like:
20 of 135 results
then total_count will just return 135, not the number of results on the page.
If you want to handle this case as well as the case where the number of results is less than the pagination result number, then I'd go with something like this:
(per_size > #users.total_count) ? #users.total_count : per_size
where per_size is the value you are setting for your per scope (docs here).
User.count would give you the count but it would hit the db. If you are using mongodb #user.length would give you the total count
Related
I need to check the total items of every page on pagination.
For example, I have 165 posts and a pagination with 4 links:
1,2,3,4
How can I discover the total items per page based on the number of pages generated?
I don't know what you're using for pagination, but the count for each page is generally set by a variable, then the remainder fills up the last page. It doesn't just output a random amount of the total on each page.
If using Kaminari, for example, there is a variable config.default_per_page.
Something like this should provide the answer.
full_pages = total_posts / default_per_page
spill_over = total_posts - (default_per_page * full_pages)
I'm trying to fetch limited amound of search result but still use of pagination. When I use next line in my repository class I get 100 result on the page.
Page<Media> findTop100ByOrderByViewCount(Pageable pageable);
If I use next line instead, then I get expected result with according to my pageable which is 10 item on each page.
Page<Media> findAllByOrderByViewCount(Pageable pageable);
I want to limit the search result. If there are 1000s of search result, I don't want to have 100s of paginated result. I want to limit my paginated limit to have max 10 page.
How can I achieve that in Spring boot? I'm using version of 2.2.2.RELEASE.
There is no shortcut for this in Spring Data.
You can wrap the call to the repository and replace the Page you receive with a modified one, which limits the total amount to 10*pagesize and removes the next value for page number 10. And probably skips the call to the database completely if the pagenumber is greater 10.
Can you please suggest how can I do pagination in click house?
Dor example in elastic search I do aggregation query like below. Here elastic search takes parameters partition number and partition size and give the result. Let's say in total we have 100 records than if we give partition size of 10 and partition number 2 then we will get 11-20 latest records.
How can we do it in click house considering data in inserting in a table.
SearchResponse response = elasticClient.prepareSearch(index)
.setTypes(documentType)
.setQuery(boolQueryBuilder)
.setSize(0)
.addAggregation(AggregationBuilders.terms("unique_uids")
.field(Constants.UID_NAME)
.includeExclude(new IncludeExclude(partition,numPartitions))
.size(Integer.MAX_VALUE))
.get();
According to specification common sql syntax for limit and offset will work:
LIMIT n, m allows you to select the first m rows from the result after skipping the first n rows. The LIMIT m OFFSET n syntax is also supported.
https://clickhouse.yandex/docs/en/query_language/select/#limit-clause
I think you're wanting to only select a subset of the result set? I haven't needed to do this yet, but seems you could specify the format you want CH to return the data in (https://clickhouse-docs.readthedocs.io/en/latest/formats/index.html) and go from there. For instance, select one of the JSON formats as shown in the ^^ documentation and then get the subset of results appropriate for your situation out of the JSON response.
I have few filters on the view page and want to show the count that matches the given conditions. Like on the product search result I have Free Shipping filter. I need the count of records matching my filters in the total record not just in the current page.
Explanation:
Suppose In the result set I have 100 records with pagination 20/page, 40 of them has free_shipping = 1. I want to show like Free Shipping(40). Currently, I do $products->where('free_shipping', 1)->count() but this gives me the result matching only in viewed records.
How can I get the total number of matching records regardless of pagination?
Thanks in advance
if Laravel Pagination is used then you can use the total() method.
Example :
$products->total();
Given I have a simple query:
List<Customer> findByEntity(String entity);
This query returns 7k records in 700ms.
Page<Customer> findByEntity(String entity, Pageable pageable);
this query returns 10 records in 1080ms. I am aware of the additional count query for pagination, but still something seems off. Also one strange thing I've noticed is that if I increase page size from 10 to 1900, response time is exactly the same around 1080 ms.
Any suggestions?
It might indeed be the count query that's expensive here. If you insist on knowing about the total number of elements matching in the collection there's unfortunately no way around that additional query. However there are two possibilities to avoid more of the overhead if you're able to sacrifice on information returned:
Using Slice as return type — Slice doesn't expose a method to find out about the total number of elements but it allows you to find out about whether a next slice is available. We avoid the count query here by reading one more element than requested and using its (non-)presence as indicator of the availability of a next slice.
Using List as return type — That will simply apply the pagination parameters to the query and return the window of elements selected. However it leaves you with no information about whether subsequent data is available.
Method with pagination runs two query:
1) select count(e.id) from Entity e //to get number of total records
2) select e from Entity e limit 10 [offset 10] //'offset 10' is used for next pages
The first query runs slow on 7k records, IMHO.
Upcoming release Ingalis of Spring Data will use improved algorithm for paginated queries (more info).
Any suggestions?
I think using a paginated query with 7k records it's useless. You should limit it.