- 1. API with NestJS #1. Controllers, routing and the module structure
- 2. API with NestJS #2. Setting up a PostgreSQL database with TypeORM
- 3. API with NestJS #3. Authenticating users with bcrypt, Passport, JWT, and cookies
- 4. API with NestJS #4. Error handling and data validation
- 5. API with NestJS #5. Serializing the response with interceptors
- 6. API with NestJS #6. Looking into dependency injection and modules
- 7. API with NestJS #7. Creating relationships with Postgres and TypeORM
- 8. API with NestJS #8. Writing unit tests
- 9. API with NestJS #9. Testing services and controllers with integration tests
- 10. API with NestJS #10. Uploading public files to Amazon S3
- 11. API with NestJS #11. Managing private files with Amazon S3
- 12. API with NestJS #12. Introduction to Elasticsearch
- 13. API with NestJS #13. Implementing refresh tokens using JWT
- 14. API with NestJS #14. Improving performance of our Postgres database with indexes
- 15. API with NestJS #15. Defining transactions with PostgreSQL and TypeORM
- 16. API with NestJS #16. Using the array data type with PostgreSQL and TypeORM
- 17. API with NestJS #17. Offset and keyset pagination with PostgreSQL and TypeORM
- 18. API with NestJS #18. Exploring the idea of microservices
- 19. API with NestJS #19. Using RabbitMQ to communicate with microservices
- 20. API with NestJS #20. Communicating with microservices using the gRPC framework
- 21. API with NestJS #21. An introduction to CQRS
- 22. API with NestJS #22. Storing JSON with PostgreSQL and TypeORM
- 23. API with NestJS #23. Implementing in-memory cache to increase the performance
- 24. API with NestJS #24. Cache with Redis. Running the app in a Node.js cluster
- 25. API with NestJS #25. Sending scheduled emails with cron and Nodemailer
- 26. API with NestJS #26. Real-time chat with WebSockets
- 27. API with NestJS #27. Introduction to GraphQL. Queries, mutations, and authentication
- 28. API with NestJS #28. Dealing in the N + 1 problem in GraphQL
- 29. API with NestJS #29. Real-time updates with GraphQL subscriptions
- 30. API with NestJS #30. Scalar types in GraphQL
- 31. API with NestJS #31. Two-factor authentication
- 32. API with NestJS #32. Introduction to Prisma with PostgreSQL
- 33. API with NestJS #33. Managing PostgreSQL relationships with Prisma
- 34. API with NestJS #34. Handling CPU-intensive tasks with queues
- 35. API with NestJS #35. Using server-side sessions instead of JSON Web Tokens
- 36. API with NestJS #36. Introduction to Stripe with React
- 37. API with NestJS #37. Using Stripe to save credit cards for future use
- 38. API with NestJS #38. Setting up recurring payments via subscriptions with Stripe
- 39. API with NestJS #39. Reacting to Stripe events with webhooks
- 40. API with NestJS #40. Confirming the email address
- 41. API with NestJS #41. Verifying phone numbers and sending SMS messages with Twilio
- 42. API with NestJS #42. Authenticating users with Google
- 43. API with NestJS #43. Introduction to MongoDB
- 44. API with NestJS #44. Implementing relationships with MongoDB
- 45. API with NestJS #45. Virtual properties with MongoDB and Mongoose
- 46. API with NestJS #46. Managing transactions with MongoDB and Mongoose
- 47. API with NestJS #47. Implementing pagination with MongoDB and Mongoose
- 48. API with NestJS #48. Definining indexes with MongoDB and Mongoose
- 49. API with NestJS #49. Updating with PUT and PATCH with MongoDB and Mongoose
- 50. API with NestJS #50. Introduction to logging with the built-in logger and TypeORM
- 51. API with NestJS #51. Health checks with Terminus and Datadog
- 52. API with NestJS #52. Generating documentation with Compodoc and JSDoc
- 53. API with NestJS #53. Implementing soft deletes with PostgreSQL and TypeORM
- 54. API with NestJS #54. Storing files inside a PostgreSQL database
- 55. API with NestJS #55. Uploading files to the server
- 56. API with NestJS #56. Authorization with roles and claims
- 57. API with NestJS #57. Composing classes with the mixin pattern
- 58. API with NestJS #58. Using ETag to implement cache and save bandwidth
- 59. API with NestJS #59. Introduction to a monorepo with Lerna and Yarn workspaces
- 60. API with NestJS #60. The OpenAPI specification and Swagger
- 61. API with NestJS #61. Dealing with circular dependencies
- 62. API with NestJS #62. Introduction to MikroORM with PostgreSQL
- 63. API with NestJS #63. Relationships with PostgreSQL and MikroORM
- 64. API with NestJS #64. Transactions with PostgreSQL and MikroORM
- 65. API with NestJS #65. Implementing soft deletes using MikroORM and filters
- 66. API with NestJS #66. Improving PostgreSQL performance with indexes using MikroORM
- 67. API with NestJS #67. Migrating to TypeORM 0.3
- 68. API with NestJS #68. Interacting with the application through REPL
- 69. API with NestJS #69. Database migrations with TypeORM
- 70. API with NestJS #70. Defining dynamic modules
- 71. API with NestJS #71. Introduction to feature flags
- 72. API with NestJS #72. Working with PostgreSQL using raw SQL queries
- 73. API with NestJS #73. One-to-one relationships with raw SQL queries
- 74. API with NestJS #74. Designing many-to-one relationships using raw SQL queries
- 75. API with NestJS #75. Many-to-many relationships using raw SQL queries
- 76. API with NestJS #76. Working with transactions using raw SQL queries
- 77. API with NestJS #77. Offset and keyset pagination with raw SQL queries
- 78. API with NestJS #78. Generating statistics using aggregate functions in raw SQL
- 79. API with NestJS #79. Implementing searching with pattern matching and raw SQL
- 80. API with NestJS #80. Updating entities with PUT and PATCH using raw SQL queries
- 81. API with NestJS #81. Soft deletes with raw SQL queries
- 82. API with NestJS #82. Introduction to indexes with raw SQL queries
- 83. API with NestJS #83. Text search with tsvector and raw SQL
- 84. API with NestJS #84. Implementing filtering using subqueries with raw SQL
- 85. API with NestJS #85. Defining constraints with raw SQL
- 86. API with NestJS #86. Logging with the built-in logger when using raw SQL
- 87. API with NestJS #87. Writing unit tests in a project with raw SQL
- 88. API with NestJS #88. Testing a project with raw SQL using integration tests
- 89. API with NestJS #89. Replacing Express with Fastify
- 90. API with NestJS #90. Using various types of SQL joins
- 91. API with NestJS #91. Dockerizing a NestJS API with Docker Compose
- 92. API with NestJS #92. Increasing the developer experience with Docker Compose
- 93. API with NestJS #93. Deploying a NestJS app with Amazon ECS and RDS
- 94. API with NestJS #94. Deploying multiple instances on AWS with a load balancer
- 95. API with NestJS #95. CI/CD with Amazon ECS and GitHub Actions
- 96. API with NestJS #96. Running unit tests with CI/CD and GitHub Actions
- 97. API with NestJS #97. Introduction to managing logs with Amazon CloudWatch
- 98. API with NestJS #98. Health checks with Terminus and Amazon ECS
- 99. API with NestJS #99. Scaling the number of application instances with Amazon ECS
- 100. API with NestJS #100. The HTTPS protocol with Route 53 and AWS Certificate Manager
- 101. API with NestJS #101. Managing sensitive data using the AWS Secrets Manager
- 102. API with NestJS #102. Writing unit tests with Prisma
- 103. API with NestJS #103. Integration tests with Prisma
- 104. API with NestJS #104. Writing transactions with Prisma
- 105. API with NestJS #105. Implementing soft deletes with Prisma and middleware
- 106. API with NestJS #106. Improving performance through indexes with Prisma
- 107. API with NestJS #107. Offset and keyset pagination with Prisma
- 108. API with NestJS #108. Date and time with Prisma and PostgreSQL
- 109. API with NestJS #109. Arrays with PostgreSQL and Prisma
- 110. API with NestJS #110. Managing JSON data with PostgreSQL and Prisma
- 111. API with NestJS #111. Constraints with PostgreSQL and Prisma
- 112. API with NestJS #112. Serializing the response with Prisma
- 113. API with NestJS #113. Logging with Prisma
- 114. API with NestJS #114. Modifying data using PUT and PATCH methods with Prisma
- 115. API with NestJS #115. Database migrations with Prisma
- 116. API with NestJS #116. REST API versioning
- 117. API with NestJS #117. CORS – Cross-Origin Resource Sharing
- 118. API with NestJS #118. Uploading and streaming videos
- 119. API with NestJS #119. Type-safe SQL queries with Kysely and PostgreSQL
- 120. API with NestJS #120. One-to-one relationships with the Kysely query builder
- 121. API with NestJS #121. Many-to-one relationships with PostgreSQL and Kysely
- 122. API with NestJS #122. Many-to-many relationships with Kysely and PostgreSQL
- 123. API with NestJS #123. SQL transactions with Kysely
- 124. API with NestJS #124. Handling SQL constraints with Kysely
- 125. API with NestJS #125. Offset and keyset pagination with Kysely
- 126. API with NestJS #126. Improving the database performance with indexes and Kysely
- 127. API with NestJS #127. Arrays with PostgreSQL and Kysely
- 128. API with NestJS #128. Managing JSON data with PostgreSQL and Kysely
- 129. API with NestJS #129. Implementing soft deletes with SQL and Kysely
- 130. API with NestJS #130. Avoiding storing sensitive information in API logs
- 131. API with NestJS #131. Unit tests with PostgreSQL and Kysely
- 132. API with NestJS #132. Handling date and time in PostgreSQL with Kysely
- 133. API with NestJS #133. Introducing database normalization with PostgreSQL and Prisma
- 134. API with NestJS #134. Aggregating statistics with PostgreSQL and Prisma
- 135. API with NestJS #135. Referential actions and foreign keys in PostgreSQL with Prisma
- 136. API with NestJS #136. Raw SQL queries with Prisma and PostgreSQL range types
- 137. API with NestJS #137. Recursive relationships with Prisma and PostgreSQL
- 138. API with NestJS #138. Filtering records with Prisma
- 139. API with NestJS #139. Using UUID as primary keys with Prisma and PostgreSQL
- 140. API with NestJS #140. Using multiple PostgreSQL schemas with Prisma
- 141. API with NestJS #141. Getting distinct records with Prisma and PostgreSQL
- 142. API with NestJS #142. A video chat with WebRTC and React
- 143. API with NestJS #143. Optimizing queries with views using PostgreSQL and Kysely
- 144. API with NestJS #144. Creating CLI applications with the Nest Commander
- 145. API with NestJS #145. Securing applications with Helmet
- 146. API with NestJS #146. Polymorphic associations with PostgreSQL and Prisma
- 147. API with NestJS #147. The data types to store money with PostgreSQL and Prisma
- 148. API with NestJS #148. Understanding the injection scopes
- 149. API with NestJS #149. Introduction to the Drizzle ORM with PostgreSQL
- 150. API with NestJS #150. One-to-one relationships with the Drizzle ORM
- 151. API with NestJS #151. Implementing many-to-one relationships with Drizzle ORM
- 152. API with NestJS #152. SQL constraints with the Drizzle ORM
- 153. API with NestJS #153. SQL transactions with the Drizzle ORM
- 154. API with NestJS #154. Many-to-many relationships with Drizzle ORM and PostgreSQL
- 155. API with NestJS #155. Offset and keyset pagination with the Drizzle ORM
- 156. API with NestJS #156. Arrays with PostgreSQL and the Drizzle ORM
- 157. API with NestJS #157. Handling JSON data with PostgreSQL and the Drizzle ORM
- 158. API with NestJS #158. Soft deletes with the Drizzle ORM
- 159. API with NestJS #159. Date and time with PostgreSQL and the Drizzle ORM
- 160. API with NestJS #160. Using views with the Drizzle ORM and PostgreSQL
- 161. API with NestJS #161. Generated columns with the Drizzle ORM and PostgreSQL
- 162. API with NestJS #162. Identity columns with the Drizzle ORM and PostgreSQL
- 163. API with NestJS #163. Full-text search with the Drizzle ORM and PostgreSQL
- 164. API with NestJS #164. Improving the performance with indexes using Drizzle ORM
- 165. API with NestJS #165. Time intervals with the Drizzle ORM and PostgreSQL
- 166. API with NestJS #166. Logging with the Drizzle ORM
- 167. API with NestJS #167. Unit tests with the Drizzle ORM
- 168. API with NestJS #168. Integration tests with the Drizzle ORM
- 169. API with NestJS #169. Unique IDs with UUIDs using Drizzle ORM and PostgreSQL
- 170. API with NestJS #170. Polymorphic associations with PostgreSQL and Drizzle ORM
- 171. API with NestJS #171. Recursive relationships with Drizzle ORM and PostgreSQL
- 172. API with NestJS #172. Database normalization with Drizzle ORM and PostgreSQL
- 173. API with NestJS #173. Storing money with Drizzle ORM and PostgreSQL
As our database grows, maintaining good performance becomes more important. Returning large amounts of data at once through our API can negatively affect efficiency. A common solution is to divide data into smaller chunks, presenting it to the user as infinite scrolling or multiple pages. In this article, we implement this approach using PostgreSQL and the Drizzle ORM. We also compare different pagination methods and their impact on performance.
Offset and limit
Let’s start by looking at a simple select query that returns all entries from a particular table.
articles.service.ts
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import { Injectable } from '@nestjs/common'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; @Injectable() export class ArticlesService { constructor(private readonly drizzleService: DrizzleService) {} getAll() { return this.drizzleService.db.select().from(databaseSchema.articles); } // ... } |
The important thing about the results above is that the order of the returned records is not guaranteed. However, when implementing pagination, we need the order to be predictable. Therefore, we should sort the results.
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this.drizzleService.db .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)); |
The initial step in implementing pagination is to restrict the number of rows in the result. We can achieve this using the limit() function.
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this.drizzleService.db .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .limit(5); |
With this approach, we fetch only five elements instead of the entire articles table. This gives us the first page of the results.
To access the second page, we need to skip a specific number of rows. We can do this using the offset() function.
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this.drizzleService.db .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .limit(5) .offset(5); |
By combining the limit() and offset() functions, we skip the first five rows and retrieve the next five rows. In this case, it returns rows with IDs from 6 to 10. Maintaining a consistent order of rows when navigating through different pages of data is essential to avoid skipping some rows or displaying them more than once.
Counting the number of rows
A typical feature is to show the user the total number of data pages. For example, if there are one hundred rows and we display twenty per page, we end up with five pages of data.
To figure this out, we need to know the total number of rows in the table. To do this, we must use the count() function.
articles.service.ts
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import { Injectable } from '@nestjs/common'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; import { count } from 'drizzle-orm'; @Injectable() export class ArticlesService { constructor(private readonly drizzleService: DrizzleService) {} async getAll() { const articlesCountResponses = await this.drizzleService.db .select({ articlesCount: count() }) .from(databaseSchema.articles); const { articlesCount } = articlesCountResponses.pop(); // ... } // ... } |
Counting the rows in the database within the same transaction as the query that fetches the data is crucial. Thanks to that, we ensure that our results remain consistent.
If you want to know more about transactions with the Drizzle ORM, check out API with NestJS #153. SQL transactions with the Drizzle ORM
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this.drizzleService.db.transaction(async (transaction) => { const articlesCountResponses = await transaction .select({ articlesCount: count() }) .from(databaseSchema.articles); const { articlesCount } = articlesCountResponses.pop(); const data = await transaction .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .limit(5) .offset(5); return { data, count: articlesCount, }; }); |
Offset pagination with NestJS
When setting up offset pagination in a REST API, users typically supply the offset and limit through query parameters. Let’s create a class to handle them.
pagination-params.dto.ts
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import { IsNumber, Min, IsOptional } from 'class-validator'; import { Type } from 'class-transformer'; export class PaginationParamsDto { @IsOptional() @Type(() => Number) @IsNumber() @Min(0) offset: number = 0; @IsOptional() @Type(() => Number) @IsNumber() @Min(1) limit: number | null = null; } |
We can set the default offset to be because it won’t affect the result of the query.
The class we created can now be used in our controller to validate the user-provided offset and limit parameters.
articles.controller.ts
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import { Controller, Get, Query } from '@nestjs/common'; import { ArticlesService } from './articles.service'; import { PaginationParamsDto } from '../utilities/pagination-params.dto'; @Controller('articles') export class ArticlesController { constructor(private readonly articlesService: ArticlesService) {} @Get() getAll(@Query() paginationParams: PaginationParamsDto) { return this.articlesService.getAll(paginationParams); } // ... } |
The last step is to add offset and limit pagination to our service.
articles.service.ts
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import { Injectable } from '@nestjs/common'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; import { asc, count } from 'drizzle-orm'; import { PaginationParamsDto } from '../utilities/pagination-params.dto'; @Injectable() export class ArticlesService { constructor(private readonly drizzleService: DrizzleService) {} getAll({ offset, limit }: PaginationParamsDto) { return this.drizzleService.db.transaction(async (transaction) => { const articlesCountResponses = await transaction .select({ articlesCount: count() }) .from(databaseSchema.articles); const { articlesCount } = articlesCountResponses[0]; const dataQuery = transaction .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .offset(offset); if (limit) { const data = await dataQuery.limit(limit); return { data, count: articlesCount, }; } const data = await dataQuery; return { data, count: articlesCount, }; }); } // ... } |
With this approach, we achieve fully functional offset-based pagination.
Advantages
Offset-based pagination is a widely used method because it is simple to implement. It allows users to easily skip multiple data pages and change the columns we sort by. As a result, it is a suitable solution for many situations.
Disadvantages
However, offset-based pagination has significant drawbacks. The primary issue is that the database needs to process all the rows skipped by the offset, which can impact performance:
- the database sorts all rows based on the specified order,
- then, it discards the number of rows defined by the offset.
Additionally, there can be consistency issues:
- user one fetches the first page of articles,
- user two creates a new article that appears on the first page,
- user one then fetches the second page.
In this scenario, user one misses the new article added to the first page and sees the last item from the first page again on the second page.
Keyset pagination
A different way to handle pagination is using the where() function to filter data instead of relying on offset(). To illustrate that, let’s start with the following query:
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this.drizzleService.db .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .limit(5); |
In the results shown, the last row has an ID of 5. We can use this to fetch articles with IDs greater than 5.
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this.drizzleService.db .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .limit(5) .where(gt(databaseSchema.articles.id, 5)); |
It’s important to use the same column for both sorting and filtering when using the where() function.
To fetch the next set of results, we need to notice that the ID of the last row is 10 and use this information when calling the where() function.
However, this reveals the biggest drawback of keyset pagination. To retrieve the following data page, we must know the ID of the last item on the previous page. This limitation prevents us from skipping multiple pages at once.
Keyset pagination with NestJS
To set up keyset pagination in NestJS, we need to begin by adding an extra query parameter.
pagination-params.dto.ts
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import { IsNumber, Min, IsOptional } from 'class-validator'; import { Type } from 'class-transformer'; export class PaginationParamsDto { @IsOptional() @Type(() => Number) @IsNumber() @Min(0) offset: number = 0; @IsOptional() @Type(() => Number) @IsNumber() @Min(1) limit: number | null = null; @IsOptional() @Type(() => Number) @IsNumber() @Min(0) idsToSkip: number = 0; } |
Now, we need to adjust our service and use the new parameter.
articles.service.ts
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import { Injectable } from '@nestjs/common'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; import { asc, count, gt } from 'drizzle-orm'; import { PaginationParamsDto } from '../utilities/pagination-params.dto'; @Injectable() export class ArticlesService { constructor(private readonly drizzleService: DrizzleService) {} getAll({ offset, limit, idsToSkip }: PaginationParamsDto) { return this.drizzleService.db.transaction(async (transaction) => { const articlesCountResponses = await transaction .select({ articlesCount: count() }) .from(databaseSchema.articles); const { articlesCount } = articlesCountResponses[0]; const dataQuery = transaction .select() .from(databaseSchema.articles) .orderBy(asc(databaseSchema.articles.id)) .offset(offset) .where(gt(databaseSchema.articles.id, idsToSkip)); if (limit) { const data = await dataQuery.limit(limit); return { data, count: articlesCount, }; } const data = await dataQuery; return { data, count: articlesCount, }; }); } // ... } |
Advantages
Keyset pagination can provide a significant performance boost compared to offset-based pagination, especially with large datasets. It also addresses the data inconsistency issues that can occur with offset pagination. When users add or remove rows, keyset pagination prevents elements from being skipped or duplicated as pages are fetched.
Disadvantages
The biggest drawback of keyset pagination is that users need to know the row ID from which to start. Fortunately, we can address this issue by combining keyset pagination with the offset-based approach.
The column used for filtering should have an index for better performance. Thankfully, PostgreSQL automatically creates an index for every primary key, so keyset pagination works efficiently with IDs.
However, sorting results by text columns can be challenging when natural sorting is required. If you want to know more, check out this question on StackOverflow.
Summary
In this article, we explored two different pagination methods that can be used with the Drizzle ORM and PostgreSQL. By examining their pros and cons, it’s clear that each approach is suitable for different scenarios. Keyset pagination, though more restrictive, offers better performance. Fortunately, mixing keyset and offset pagination allows us to handle various cases, leveraging the benefits of both methods.