Unique indices
You can create a database index for a specific column by using @Index
on a column you want to make an index. You can create indices for any columns of your entity. Example:
import { Entity, PrimaryGeneratedColumn, Column, Index } from "typeorm"
@Entity()
export class User {
@PrimaryGeneratedColumn()
id: number
@Index()
@Column()
firstName: string
@Column()
@Index()
lastName: string
}
You can also specify an index name:
import { Entity, PrimaryGeneratedColumn, Column, Index } from "typeorm"
@Entity()
export class User {
@PrimaryGeneratedColumn()
id: number
@Index("name1-idx")
@Column()
firstName: string
@Column()
@Index("name2-idx")
lastName: string
}
Unique indices
To create an unique index you need to specify { unique: true }
in the index options:
Note: CockroachDB stores unique indices as
UNIQUE
constraints
import { Entity, PrimaryGeneratedColumn, Column, Index } from "typeorm"
@Entity()
export class User {
@PrimaryGeneratedColumn()
id: number
@Index({ unique: true })
@Column()
firstName: string
@Column()
@Index({ unique: true })
lastName: string
}
Indices with multiple columns
To create an index with multiple columns you need to put @Index
on the entity itself and specify all column property names which should be included in the index. Example:
import { Entity, PrimaryGeneratedColumn, Column, Index } from "typeorm"
@Entity()
@Index(["firstName", "lastName"])
@Index(["firstName", "middleName", "lastName"], { unique: true })
export class User {
@PrimaryGeneratedColumn()
id: number
@Column()
firstName: string
@Column()
middleName: string
@Column()
lastName: string
}