Describe the algorithm for retrieving a specific page from the database with filtering and sorting.

The algorithm for retrieving a specific page from a database with filtering and sorting typically involves the following steps:

1. Getting request parameters:

   • Page number
   • Page size
   • Filtering criteria (e.g., fields and values for WHERE)
   • Sorting criteria (e.g., field and direction ASC/DESC)

2. Forming the SQL query:

   • Add filtering conditions to the WHERE clause
   • Add sorting to the ORDER BY clause
   • Add pagination using LIMIT and OFFSET:
     • OFFSET = (page_number - 1) * page_size
     • LIMIT = page_size

3. Executing the query against the database and obtaining the result

4. Optional:

   • Get the total number of records with such filters to display the total number of pages

Example SQL query:

SELECT * FROM products
WHERE category = 'books' AND price > 100
ORDER BY price DESC
LIMIT 10 OFFSET 20;

Here, we retrieve the third page (if page size is 10), filtered by category and price, sorted by descending price.

This approach allows efficient loading of only the needed data chunk, minimizing network and client load.