查找选项

• 基本选项
• 高级选项

基本选项

所有仓库和管理器的 .find* 方法接受一些特殊选项，您可以在不使用 QueryBuilder 的情况下使用这些选项查询所需的数据：

• select - 指示必须选择主对象的哪些属性

userRepository.find({
    select: {
        firstName: true,
        lastName: true,
    },
})

将执行以下查询：

SELECT "firstName", "lastName" FROM "user"

• relations - 需要与主实体一起加载的关系。也可以加载子关系（join 和 leftJoinAndSelect 的简写）

userRepository.find({
    relations: {
        profile: true,
        photos: true,
        videos: true,
    },
})
userRepository.find({
    relations: {
        profile: true,
        photos: true,
        videos: {
            videoAttributes: true,
        },
    },
})

将执行以下查询：

SELECT * FROM "user"
LEFT JOIN "profile" ON "profile"."id" = "user"."profileId"
LEFT JOIN "photos" ON "photos"."id" = "user"."photoId"
LEFT JOIN "videos" ON "videos"."id" = "user"."videoId"

SELECT * FROM "user"
LEFT JOIN "profile" ON "profile"."id" = "user"."profileId"
LEFT JOIN "photos" ON "photos"."id" = "user"."photoId"
LEFT JOIN "videos" ON "videos"."id" = "user"."videoId"
LEFT JOIN "video_attributes" ON "video_attributes"."id" = "videos"."video_attributesId"

• where - 应该根据哪些简单条件查询实体。

userRepository.find({
    where: {
        firstName: "Timber",
        lastName: "Saw",
    },
})

将执行以下查询：

SELECT * FROM "user"
WHERE "firstName" = 'Timber' AND "lastName" = 'Saw'

从嵌入式实体的列进行查询时，应该按照定义它们的层次结构进行。示例：

userRepository.find({
    relations: {
        project: true,
    },
    where: {
        project: {
            name: "TypeORM",
            initials: "TORM",
        },
    },
})

将执行以下查询：

SELECT * FROM "user"
LEFT JOIN "project" ON "project"."id" = "user"."projectId"
WHERE "project"."name" = 'TypeORM' AND "project"."initials" = 'TORM'

使用 OR 运算符进行查询：

userRepository.find({
    where: [
        { firstName: "Timber", lastName: "Saw" },
        { firstName: "Stan", lastName: "Lee" },
    ],
})

将执行以下查询：

SELECT * FROM "user" WHERE ("firstName" = 'Timber' AND "lastName" = 'Saw') OR ("firstName" = 'Stan' AND "lastName" = 'Lee')

• order - 选择顺序。

userRepository.find({
    order: {
        name: "ASC",
        id: "DESC",
    },
})

将执行以下查询：

SELECT * FROM "user"
ORDER BY "name" ASC, "id" DESC

• withDeleted - 包括已使用 softDelete 或 softRemove 软删除的实体，例如设置了 @DeleteDateColumn 列的实体。默认情况下，软删除的实体不包括在内。

userRepository.find({
    withDeleted: true,
})

返回多个实体的 find* 方法（find、findBy、findAndCount、findAndCountBy）还接受以下选项：

• skip - 偏移（分页）从哪里获取实体。

userRepository.find({
    skip: 5,
})

SELECT * FROM "user"
OFFSET 5

• take - 限制（分页）- 应该获取的最大实体数量。

userRepository.find({
    take: 10,
})

将执行以下查询：

SELECT * FROM "user"
LIMIT 10

** skip 和 take 应该一起使用

** 如果您正在使用带有 MSSQL 的 typeorm，并希望使用 take 或 limit，您需要使用 order，否则您将收到以下错误：'Invalid usage of the option NEXT in the FETCH statement.'

userRepository.find({
    order: {
        columnName: "ASC",
    },
    skip: 0,
    take: 10,
})

将执行以下查询：

SELECT * FROM "user"
ORDER BY "columnName" ASC
LIMIT 10 OFFSET 0

• cache - 启用或禁用查询结果缓存。有关更多信息和选项，请参阅 缓存。

userRepository.find({
    cache: true,
})

• lock - 为查询启用锁定机制。只能在 findOne 和 findOneBy 方法中使用。 lock 是一个可以定义为：

{ mode: "optimistic", version: number | Date }

或

{
    mode: "pessimistic_read" |
        "pessimistic_write" |
        "dirty_read" |
        /*
            "pessimistic_partial_write" and "pessimistic_write_or_fail" are deprecated and
            will be removed in a future version.

            Use onLocked instead.
         */
        "pessimistic_partial_write" |
        "pessimistic_write_or_fail" |
        "for_no_key_update" |
        "for_key_share",

    tables: string[],
    onLocked: "nowait" | "skip_locked"
}

例如：

userRepository.findOne({
    where: {
        id: 1,
    },
    lock: { mode: "optimistic", version: 1 },
})

有关更多信息，请参阅 锁定模式

查找选项的完整示例：

userRepository.find({
    select: {
        firstName: true,
        lastName: true,
    },
    relations: {
        profile: true,
        photos: true,
        videos: true,
    },
    where: {
        firstName: "Timber",
        lastName: "Saw",
        profile: {
            userName: "tshaw",
        },
    },
    order: {
        name: "ASC",
        id: "DESC",
    },
    skip: 5,
    take: 10,
    cache: true,
})

无参数查找：

userRepository.find()

将执行以下查询：

SELECT * FROM "user"

高级选项

TypeORM 提供了许多内置运算符，可用于创建更复杂的比较：

• Not

import { Not } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: Not("About #1"),
})

将执行以下查询：

SELECT * FROM "post" WHERE "title" != 'About #1'

• LessThan

import { LessThan } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: LessThan(10),
})

将执行以下查询：

SELECT * FROM "post" WHERE "likes" < 10

• LessThanOrEqual

import { LessThanOrEqual } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: LessThanOrEqual(10),
})

将执行以下查询：

SELECT * FROM "post" WHERE "likes" <= 10

• MoreThan

import { MoreThan } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: MoreThan(10),
})

将执行以下查询：

SELECT * FROM "post" WHERE "likes" > 10

• MoreThanOrEqual

import { MoreThanOrEqual } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: MoreThanOrEqual(10),
})

将执行以下查询：

SELECT * FROM "post" WHERE "likes" >= 10

• Equal

import { Equal } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: Equal("About #2"),
})

将执行以下查询：

SELECT * FROM "post" WHERE "title" = 'About #2'

• Like

import { Like } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: Like("%out #%"),
})

将执行以下查询：

SELECT * FROM "post" WHERE "title" LIKE '%out #%'

• ILike

import { ILike } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: ILike("%out #%"),
})

将执行以下查询：

SELECT * FROM "post" WHERE "title" ILIKE '%out #%'

• Between

import { Between } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: Between(1, 10),
})

将执行以下查询：

SELECT * FROM "post" WHERE "likes" BETWEEN 1 AND 10

• In

import { In } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: In(["About #2", "About #3"]),
})

将执行以下查询：

SELECT * FROM "post" WHERE "title" IN ('About #2','About #3')

• Any

import { Any } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: Any(["About #2", "About #3"]),
})

将执行以下查询（Postgres 符号）：

```sql
SELECT * FROM "post" WHERE "title" = ANY(['About #2','About #3'])

• IsNull

import { IsNull } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    title: IsNull(),
})

将执行以下查询：

SELECT * FROM "post" WHERE "title" IS NULL

• ArrayContains

import { ArrayContains } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    categories: ArrayContains(["TypeScript"]),
})

将执行以下查询：

SELECT * FROM "post" WHERE "categories" @> '{TypeScript}'

• ArrayContainedBy

import { ArrayContainedBy } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    categories: ArrayContainedBy(["TypeScript"]),
})

将执行以下查询：

SELECT * FROM "post" WHERE "categories" <@ '{TypeScript}'

• ArrayOverlap

import { ArrayOverlap } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    categories: ArrayOverlap(["TypeScript"]),
})

将执行以下查询：

SELECT * FROM "post" WHERE "categories" && '{TypeScript}'

• Raw

import { Raw } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: Raw("dislikes - 4"),
})

将执行以下查询：

SELECT * FROM "post" WHERE "likes" = "dislikes" - 4

在最简单的情况下，原始查询将直接插入等号后。但是，您还可以使用函数完全重写比较逻辑。

import { Raw } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    currentDate: Raw((alias) => `${alias} > NOW()`),
})

将执行以下查询：

SELECT * FROM "post" WHERE "currentDate" > NOW()

如果您需要提供用户输入，您不应将用户输入直接包含在查询中，因为这可能会产生 SQL 注入漏洞。相反，您可以使用 Raw 函数的第二个参数提供一个参数列表以绑定到查询。

import { Raw } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    currentDate: Raw((alias) => `${alias} > :date`, { date: "2020-10-06" }),
})

将执行以下查询：

SELECT * FROM "post" WHERE "currentDate" > '2020-10-06'

如果您需要提供的用户输入是数组，则可以使用特殊表达式语法将它们绑定为 SQL 语句中的值列表：

import { Raw } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findby({
    title: Raw((alias) => `${alias} IN (:...titles)`, {
        titles: [
            "Go To Statement Considered Harmful",
            "Structured Programming",
        ],
    }),
})

将执行以下查询：

SELECT * FROM "post" WHERE "titles" IN ('Go To Statement Considered Harmful', 'Structured Programming')

组合高级选项

您还可以将这些运算符与 Not 运算符组合：

import { Not, MoreThan, Equal } from "typeorm"

const loadedPosts = await dataSource.getRepository(Post).findBy({
    likes: Not(MoreThan(10)),
    title: Not(Equal("About #2")),
})

将执行以下查询：

SELECT * FROM "post" WHERE NOT("likes" > 10) AND NOT("title" = 'About #2')