Drizzle ORM is designed to be a thin typed layer on top of SQL.
We truly believe we’ve designed the best way to operate an SQL database from TypeScript and it’s time to make it better.
Relational queries are meant to provide you with a great developer experience for querying
nested relational data from an SQL database, avoiding multiple joins and complex data mappings.
It is an extension to the existing schema definition and query builder.
You can opt-in to use it based on your needs.
We’ve made sure you have both the best-in-class developer experience and performance.
index.ts
schema.ts
⚠️ If you have SQL schema declared in multiple files you can do it like that
index.ts
schema1.ts
schema2.ts
Modes
Drizzle relational queries always generate exactly one SQL statement to run on the database and it has certain caveats.
To have best in class support for every database out there we’ve introduced modes.
Drizzle relational queries use lateral joins of subqueries under the hood and for now PlanetScale does not support them.
When using mysql2 driver with regular MySQL database — you should specify mode: "default"
When using mysql2 driver with PlanetScale — you need to specify mode: "planetscale"
Querying
Relational queries are an extension to Drizzle’s original query builder.
You need to provide all tables and relations from your schema file/files upon drizzle()
initialization and then just use the db.query API.
drizzle import path depends on the database driver you’re using.
index.ts
schema.ts
Drizzle provides .findMany() and .findFirst() APIs.
Find many
Find first
.findFirst() will add limit 1 to the query.
Include relations
With operator lets you combine data from multiple related tables and properly aggregate results.
Getting all posts with comments:
Getting first post with comments:
You can chain nested with statements as much as necessary.
For any nested with queries Drizzle will infer types using Core Type API.
Get all users with posts. Each post should contain a list of comments:
Partial fields select
columns parameter lets you include or omit columns you want to get from the database.
Drizzle performs partial selects on the query level, no additional data is transferred from the database.
Keep in mind that a single SQL statement is outputted by Drizzle.
Get all posts with just id, content and include comments:
Get all posts without content:
When both true and false select options are present, all false options are ignored.
If you include the name field and exclude the id field, id exclusion will be redundant,
all fields apart from name would be excluded anyways.
Exclude and Include fields in the same query:
Only include columns from nested relations:
Nested partial fields select
Just like with partial select, you can include or exclude columns of nested relations:
Select filters
Just like in our SQL-like query builder,
relational queries API lets you define filters and conditions with the list of our operators.
You can either import them from drizzle-orm or use from the callback syntax:
Find post with id=1 and comments that were created before particular date:
Limit & Offset
Drizzle ORM provides limit & offset API for queries and for the nested entities.
Find 5 posts:
Find posts and get 3 comments at most:
IMPORTANT
offset is only available for top level query.
Find posts with comments from the 5th to the 10th post:
Order By
Drizzle provides API for ordering in the relational query builder.
You can use same ordering core API or use
order by operator from the callback with no imports.
Order by asc + desc:
Include custom fields
Relational query API lets you add custom additional fields.
It’s useful when you need to retrieve data and apply additional functions to it.
IMPORTANT
As of now aggregations are not supported in extras, please use core queries for that.
lowerName as a key will be included to all fields in returned object.
IMPORTANT
You have to explicitly specify .as("<name_for_column>")
To retrieve all users with groups, but with the fullName field included (which is a concatenation of firstName and lastName),
you can use the following query with the Drizzle relational query builder.
To retrieve all posts with comments and add an additional field to calculate the size of the post content and the size of each comment content:
Prepared statements
Prepared statements are designed to massively improve query performance — see here.
In this section, you can learn how to define placeholders and execute prepared statements
using the Drizzle relational query builder.