视图

视图声明

您可以通过多种方式在 Drizzle ORM 中声明视图。

你可以声明需要创建的视图，或者声明已存在于数据库中的视图。

你可以使用内联 query builder 语法、独立的 query builder 和原始的 sql 操作符来声明视图。

当使用内联或独立的查询构建器创建视图时，视图列的架构将自动推断，但如果使用 sql，则必须显式声明视图列的架构。

声明视图

PostgreSQL

MySQL

SQLite

import { pgTable, pgView, serial, text, timestamp } from "drizzle-orm/pg-core";

export const user = pgTable("user", {
  id: serial(),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: timestamp("created_at"),
  updatedAt: timestamp("updated_at"),
});

export const userView = pgView("user_view").as((qb) => qb.select().from(user));
export const customersView = pgView("customers_view").as((qb) => qb.select().from(user).where(eq(user.role, "customer")));

CREATE VIEW "user_view" AS SELECT * FROM "user";
CREATE VIEW "customers_view" AS SELECT * FROM "user" WHERE "role" = 'customer';

import { text, mysqlTable, mysqlView, int, timestamp } from "drizzle-orm/mysql-core";

export const user = mysqlTable("user", {
  id: int().primaryKey().autoincrement(),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: timestamp("created_at"),
  updatedAt: timestamp("updated_at"),
});

export const userView = mysqlView("user_view").as((qb) => qb.select().from(user));
export const customersView = mysqlView("customers_view").as((qb) => qb.select().from(user).where(eq(user.role, "customer")));

CREATE VIEW "user_view" AS SELECT * FROM "user";
CREATE VIEW "customers_view" AS SELECT * FROM "user" WHERE "role" = 'customer';

import { integer, text, sqliteView, sqliteTable } from "drizzle-orm/sqlite-core";

export const user = sqliteTable("user", {
  id: integer().primaryKey({ autoIncrement: true }),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: integer("created_at"),
  updatedAt: integer("updated_at"),
});

export const userView = sqliteView("user_view").as((qb) => qb.select().from(user));
export const customersView = sqliteView("customers_view").as((qb) => qb.select().from(user).where(eq(user.role, "customer")));

CREATE VIEW "user_view" AS SELECT * FROM "user";
CREATE VIEW "customers_view" AS SELECT * FROM "user" WHERE "role" = 'customer';

如果你需要一个列的子集，你可以在查询构建器中使用 .select({ ... }) 方法，如下所示：

export const customersView = pgView("customers_view").as((qb) => {
  return qb
    .select({
      id: user.id,
      name: user.name,
      email: user.email,
    })
    .from(user);
});

CREATE VIEW "customers_view" AS SELECT "id", "name", "email" FROM "user" WHERE "role" = 'customer';

你也可以使用 独立的查询构建器 声明视图，它的工作方式完全相同：

PostgreSQL

MySQL

SQLite

import { pgTable, pgView, serial, text, timestamp, QueryBuilder} from "drizzle-orm/pg-core";

const qb = new QueryBuilder();

export const user = pgTable("user", {
  id: serial(),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: timestamp("created_at"),
  updatedAt: timestamp("updated_at"),
});

export const userView = pgView("user_view").as(qb.select().from(user));
export const customersView = pgView("customers_view").as(qb.select().from(user).where(eq(user.role, "customer")));

CREATE VIEW "user_view" AS SELECT * FROM "user";
CREATE VIEW "customers_view" AS SELECT * FROM "user" WHERE "role" = 'customer';

import { text, mysqlTable, mysqlView, int, timestamp, QueryBuilder } from "drizzle-orm/mysql-core";

const qb = new QueryBuilder();

export const user = mysqlTable("user", {
  id: int().primaryKey().autoincrement(),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: timestamp("created_at"),
  updatedAt: timestamp("updated_at"),
});

export const userView = mysqlView("user_view").as(qb.select().from(user));
export const customersView = mysqlView("customers_view").as(qb.select().from(user).where(eq(user.role, "customer")));

CREATE VIEW "user_view" AS SELECT * FROM "user";
CREATE VIEW "customers_view" AS SELECT * FROM "user" WHERE "role" = 'customer';

import { integer, text, sqliteView, sqliteTable, QueryBuilder } from "drizzle-orm/sqlite-core";

const qb = new QueryBuilder();

export const user = sqliteTable("user", {
  id: integer().primaryKey({ autoIncrement: true }),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: integer("created_at"),
  updatedAt: integer("updated_at"),
});

export const userView = sqliteView("user_view").as((qb) => qb.select().from(user));
export const customerView = sqliteView("customers_view").as((qb) => qb.select().from(user).where(eq(user.role, "customer")));

CREATE VIEW "user_view" AS SELECT * FROM "user";
CREATE VIEW "customers_view" AS SELECT * FROM "user" WHERE "role" = 'customer';

使用原始 SQL 声明视图

每当你需要使用查询构建器不支持的语法声明视图时，你可以直接使用 sql 操作符并显式指定视图列的架构。

// 常规视图
const newYorkers = pgView('new_yorkers', {
  id: serial('id').primaryKey(),
  name: text('name').notNull(),
  cityId: integer('city_id').notNull(),
}).as(sql`select * from ${users} where ${eq(users.cityId, 1)}`);

// 物化视图
const newYorkers = pgMaterializedView('new_yorkers', {
  id: serial('id').primaryKey(),
  name: text('name').notNull(),
  cityId: integer('city_id').notNull(),
}).as(sql`select * from ${users} where ${eq(users.cityId, 1)}`);

声明已存在的视图

当你获得对数据库中现有视图的只读访问权限时，可使用 .existing() 视图配置， drizzle-kit 将忽略并不会在生成的迁移中生成 create view 语句。

export const user = pgTable("user", {
  id: serial(),
  name: text(),
  email: text(),
  password: text(),
  role: text().$type<"admin" | "customer">(),
  createdAt: timestamp("created_at"),
  updatedAt: timestamp("updated_at"),
});

// 常规视图
export const trimmedUser = pgView("trimmed_user", {
  id: serial("id"),
  name: text("name"),
  email: text("email"),
}).existing();

// 物化视图不会有任何区别，但你可以为一致性使用它
export const trimmedUser = pgMaterializedView("trimmed_user", {
  id: serial("id"),
  name: text("name"),
  email: text("email"),
}).existing();

物化视图

PostgreSQL

MySQL

SQLite

根据官方文档，PostgreSQL 具有 常规 和 物化 视图。

PostgreSQL 中的物化视图像视图一样使用规则系统，但以表格形式持久化结果。

Drizzle ORM 原生支持 PostgreSQL 物化视图：

const newYorkers = pgMaterializedView('new_yorkers').as((qb) => qb.select().from(users).where(eq(users.cityId, 1)));

CREATE MATERIALIZED VIEW "new_yorkers" AS SELECT * FROM "users";

你可以在应用程序运行时刷新物化视图：

await db.refreshMaterializedView(newYorkers);

await db.refreshMaterializedView(newYorkers).concurrently();

await db.refreshMaterializedView(newYorkers).withNoData();

扩展示例

查询中的所有参数将被内联，而不是替换为 $1、$2 等。

// 常规视图
const newYorkers = pgView('new_yorkers')
  .with({
    checkOption: 'cascaded',
    securityBarrier: true,
    securityInvoker: true,
  })
  .as((qb) => {
    const sq = qb
      .$with('sq')
      .as(
        qb.select({ userId: users.id, cityId: cities.id })
          .from(users)
          .leftJoin(cities, eq(cities.id, users.homeCity))
          .where(sql`${users.age1} > 18`),
      );
    return qb.with(sq).select().from(sq).where(sql`${users.homeCity} = 1`);
  });

// 物化视图
const newYorkers2 = pgMaterializedView('new_yorkers')
  .using('btree')
  .with({
    fillfactor: 90,
    toast_tuple_target: 0.5,
    autovacuum_enabled: true,
    ...
  })
  .tablespace('custom_tablespace')
  .withNoData()
  .as((qb) => {
    const sq = qb
      .$with('sq')
      .as(
        qb.select({ userId: users.id, cityId: cities.id })
          .from(users)
          .leftJoin(cities, eq(cities.id, users.homeCity))
          .where(sql`${users.age1} > 18`),
      );
    return qb.with(sq).select().from(sq).where(sql`${users.homeCity} = 1`);
  });