export const metadata = { title: ${pageNumber} Data Model Database Index, }

{metadata.title}

In this chapter, you’ll learn how to define a database index on a data model.

You can also define an index on a property as explained in the Properties chapter.

Define Database Index on Data Model

A data model has an indexes method that defines database indices on its properties.

The index can be on multiple columns (composite index). For example:

export const dataModelIndexHighlights = [ ["7", "indexes", "Define indices on the data model's properties."], ["9", "on", "Specify the properties to define the index on."] ]

import { model } from "@medusajs/framework/utils"

const MyCustom = model.define("my_custom", {
  id: model.id().primaryKey(),
  name: model.text(),
  age: model.number(),
}).indexes([
  {
    on: ["name", "age"],
  },
])

export default MyCustom

The indexes method receives an array of indices as a parameter. Each index is an object with a required on property indicating the properties to apply the index on.

In the above example, you define a composite index on the name and age properties.

Index Conditions

An index can have conditions. For example:

export const conditionHighlights = [ ["10", "where", "Specify conditions on properties."], ["11", "age", "Create the index when age is 30."] ]

import { model } from "@medusajs/framework/utils"

const MyCustom = model.define("my_custom", {
  id: model.id().primaryKey(),
  name: model.text(),
  age: model.number(),
}).indexes([
  {
    on: ["name", "age"],
    where: {
      age: 30,
    },
  },
])

export default MyCustom

The index object passed to indexes accepts a where property whose value is an object of conditions. The object's key is a property's name, and its value is the condition on that property.

In the example above, the composite index is created on the name and age properties when the age's value is 30.

A property's condition can be a negation. For example:

export const negationHighlights = [ ["12", "$ne", "Create the index when age is not null."] ]

import { model } from "@medusajs/framework/utils"

const MyCustom = model.define("my_custom", {
  id: model.id().primaryKey(),
  name: model.text(),
  age: model.number().nullable(),
}).indexes([
  {
    on: ["name", "age"],
    where: {
      age: {
        $ne: null,
      },
    },
  },
])

export default MyCustom

A property's value in where can be an object having a $ne property. $ne's value indicates what the specified property's value shouldn't be.

In the example above, the composite index is created on the name and age properties when age's value is not null.

Unique Database Index

The object passed to indexes accepts a unique property indicating that the created index must be a unique index.

For example:

export const uniqueHighlights = [ ["10", "unique", "Specify if the index is a unique index."] ]

import { model } from "@medusajs/framework/utils"

const MyCustom = model.define("my_custom", {
  id: model.id().primaryKey(),
  name: model.text(),
  age: model.number(),
}).indexes([
  {
    on: ["name", "age"],
    unique: true,
  },
])

export default MyCustom

This creates a unique composite index on the name and age properties.