MongoDB 子文档嵌套文档验证

MongoDB 是一种流行的 NoSQL 数据库，它以其灵活的文档模型和强大的查询功能而闻名。在 MongoDB 中，我们可以使用子文档和嵌套文档来组织和存储复杂的数据结构。子文档是文档中的一个字段，它包含一个完整的文档作为其值。嵌套文档则是在一个文档内部嵌套另一个文档。

javascript
{
  "_id": ObjectId("60a6cb2ebea2dd001f0e7d1b"),
  "username": "john_doe",
  "email": "john@example.com",
  "articles": [
    {
      "title": "MongoDB 基础入门",
      "content": "MongoDB 是一个开源的文档数据库。",
      "created_at": ISODate("2021-05-20T10:00:00Z")
    },
    {
      "title": "MongoDB 高级查询",
      "content": "MongoDB 提供了强大的查询功能。",
      "created_at": ISODate("2021-05-25T14:30:00Z")
    }
  ]
}

javascript
db.createCollection("users", {
  validator: {
    $jsonSchema: {
      bsonType: "object",
      required: ["username", "email", "articles"],
      properties: {
        username: {
          bsonType: "string"
        },
        email: {
          bsonType: "string"
        },
        articles: {
          bsonType: "array",
          items: {
            bsonType: "object",
            required: ["title", "content", "created_at"],
            properties: {
              title: {
                bsonType: "string",
                maxLength: 100
              },
              content: {
                bsonType: "string",
                maxLength: 1000
              },
              created_at: {
                bsonType: "date"
              }
            }
          }
        }
      }
    }
  },
  validationAction: "error"
})

javascript
db.createCollection("users", {
  validator: {
    $jsonSchema: {
      bsonType: "object",
      required: ["username", "email", "articles"],
      properties: {
        username: {
          bsonType: "string"
        },
        email: {
          bsonType: "string"
        },
        articles: {
          bsonType: "array",
          minItems: 1,
          items: {
            bsonType: "object",
            required: ["title", "content", "created_at"],
            properties: {
              title: {
                bsonType: "string",
                maxLength: 100
              },
              content: {
                bsonType: "string",
                maxLength: 1000
              },
              created_at: {
                bsonType: "date"
              }
            }
          }
        }
      }
    }
  },
  validationAction: "error"
})