Drizzle ORM - Unique and Case-Insensitive Email Handling

Drizzle | Unique and Case-Insensitive Email Handling

This guide assumes familiarity with:

Get started with PostgreSQL, MySQL and SQLite
Indexes
Insert statement and Select method
sql operator
You should have [email protected] and [email protected] or higher.

PostgreSQL

To implement a unique and case-insensitive email handling in PostgreSQL with Drizzle, you can create a unique index on the lowercased email column. This way, you can ensure that the email is unique regardless of the case.

Drizzle has simple and flexible API, which lets you easily create such an index using SQL-like syntax:

schema.ts

migration.sql

import { SQL, sql } from 'drizzle-orm';
import { pgTable, serial, text, uniqueIndex } from 'drizzle-orm/pg-core';

export const users = pgTable(
  'users',
  {
    id: serial('id').primaryKey(),
    name: text('name').notNull(),
    email: text('email').notNull(),
  },
  (table) => [
    // uniqueIndex('emailUniqueIndex').on(sql`lower(${table.email})`),
    uniqueIndex('emailUniqueIndex').on(lower(table.email)),
  ],
);

// custom lower function
export function lower(email: AnyPgColumn): SQL {
  return sql`lower(${email})`;
}

CREATE TABLE IF NOT EXISTS "users" (
  "id" serial PRIMARY KEY NOT NULL,
  "name" text NOT NULL,
  "email" text NOT NULL
);
--> statement-breakpoint
CREATE UNIQUE INDEX IF NOT EXISTS "emailUniqueIndex" ON "users" USING btree (lower("email"));

This is how you can select user by email with lower function:

import { eq } from 'drizzle-orm';
import { lower, users } from './schema';

const db = drizzle(...);

const findUserByEmail = async (email: string) => {
  return await db
    .select()
    .from(users)
    .where(eq(lower(users.email), email.toLowerCase()));
};

select * from "users" where lower(email) = '[email protected]';

MySQL

In MySQL, the default collation setting for string comparison is case-insensitive, which means that when performing operations like searching or comparing strings in SQL queries, the case of the characters does not affect the results. However, because collation settings can vary and may be configured to be case-sensitive, we will explicitly ensure that the email is unique regardless of case by creating a unique index on the lowercased email column.

Drizzle has simple and flexible API, which lets you easily create such an index using SQL-like syntax:

schema.ts

migration.sql

import { SQL, sql } from 'drizzle-orm';
import { AnyMySqlColumn, mysqlTable, serial, uniqueIndex, varchar } from 'drizzle-orm/mysql-core';

export const users = mysqlTable(
  'users',
  {
    id: serial('id').primaryKey(),
    name: varchar('name', { length: 255 }).notNull(),
    email: varchar('email', { length: 255 }).notNull(),
  },
  (table) => [
    // uniqueIndex('emailUniqueIndex').on(sql`(lower(${table.email}))`),
    uniqueIndex('emailUniqueIndex').on(lower(table.email)),
  ]
);

// custom lower function
export function lower(email: AnyMySqlColumn): SQL {
  return sql`(lower(${email}))`;
}

CREATE TABLE `users` (
    `id` serial AUTO_INCREMENT NOT NULL,
    `name` varchar(255) NOT NULL,
    `email` varchar(255) NOT NULL,
    CONSTRAINT `users_id` PRIMARY KEY(`id`),
    CONSTRAINT `emailUniqueIndex` UNIQUE((lower(`email`)))
);

IMPORTANT

Functional indexes are supported in MySQL starting from version 8.0.13. For the correct syntax, the expression should be enclosed in parentheses, for example, (lower(column)).

This is how you can select user by email with lower function:

import { eq } from 'drizzle-orm';
import { lower, users } from './schema';

const db = drizzle(...);

const findUserByEmail = async (email: string) => {
  return await db
    .select()
    .from(users)
    .where(eq(lower(users.email), email.toLowerCase()));
};

select * from `users` where lower(email) = '[email protected]';

SQLite

To implement a unique and case-insensitive email handling in SQLite with Drizzle, you can create a unique index on the lowercased email column. This way, you can ensure that the email is unique regardless of the case.

Drizzle has simple and flexible API, which lets you easily create such an index using SQL-like syntax:

schema.ts

migration.sql

import { SQL, sql } from 'drizzle-orm';
import { AnySQLiteColumn, integer, sqliteTable, text, uniqueIndex } from 'drizzle-orm/sqlite-core';

export const users = sqliteTable(
  'users',
  {
    id: integer('id').primaryKey(),
    name: text('name').notNull(),
    email: text('email').notNull(),
  },
  (table) => [
    // uniqueIndex('emailUniqueIndex').on(sql`lower(${table.email})`),
    uniqueIndex('emailUniqueIndex').on(lower(table.email)),
  ]
);

// custom lower function
export function lower(email: AnySQLiteColumn): SQL {
  return sql`lower(${email})`;
}

CREATE TABLE `users` (
    `id` integer PRIMARY KEY NOT NULL,
    `name` text NOT NULL,
    `email` text NOT NULL
);
--> statement-breakpoint
CREATE UNIQUE INDEX `emailUniqueIndex` ON `users` (lower(`email`));

This is how you can select user by email with lower function:

import { eq } from 'drizzle-orm';
import { lower, users } from './schema';

const db = drizzle(...);

const findUserByEmail = async (email: string) => {
  return await db
    .select()
    .from(users)
    .where(eq(lower(users.email), email.toLowerCase()));
};

select * from "users" where lower(email) = '[email protected]';