当发生唯一约束错误时，我如何跳过sequelize node.js中的主键自动递增当我使用Postman将相同的用户名输入两次时，我的程序以正确的方式运行，但问题是递增的主键仍在继续。例如当我插入另一个不同的用户名值时，程序会像预期的那样跳转到一个连续的主键，所以，如何才能停止自动递增id，因为我已限制不能在数据库中插入重复的用户名值

/* DATABASE CONFIGURATION FILE */
    const { Sequelize, QueryTypes, DataTypes, Op, UniqueConstraintError, ValidationErrorItem } = require(`sequelize`);

    const sequelize = new Sequelize(`tutorialdb`, `root`, ``, {
        host: `localhost`,
        dialect: `mysql`,
        logging: true,
        pool: {
            max: 5,
            min: 0,
            acquire: 30000,
            idle: 10000,
        },
    });

    sequelize
    .authenticate()
    .then(() => {
    console.log(`Connection has been established successfully...`);
    })
    .catch((err) => {
    console.log(`Unable to connect to the database: `, err);
    });

    const db = {};
    db.Sequelize = Sequelize;
    db.sequelize = sequelize;
    db.QueryTypes = QueryTypes;
    db.DataTypes = DataTypes;
    db.Op = Op;
    db.ValidationErrorItem = ValidationErrorItem;
    db.UniqueConstraintError = UniqueConstraintError;

    db.postModel = require(`../models/post.model.jsx`)(sequelize, DataTypes);

    db.sequelize.sync({ force: false, alter: false, match: /tutorialdb$/ }).then(() => {
    console.log(`Tables were synced successfully`);
    });

    module.exports = db;

    /* Model definition File */
    module.exports = (sequelize, DataTypes) => {
    const Post = sequelize.define(
    `post`,
    {
        id: {
            type: DataTypes.INTEGER.UNSIGNED,
            allowNull: false,
            primaryKey: true,
            autoIncrement: true,
        },
        title: {
            type: DataTypes.STRING(30),
            allowNull: false,
            validate: {
                notEmpty: {
                    args: true,
                    msg: `Title is required`,
                },
                len: {
                    args: [3, 50],
                    msg: `Title must between 3 and 30 characters`,
                },
            },
        },
        text: {
            type: DataTypes.STRING(100),
            allowNull: false,
            validate: {
                notEmpty: {
                    args: true,
                    msg: `Text is required`,
                },
                len: {
                    args: [5, 100],
                    msg: `Text must between 5 and 100 characters`,
                },
            },
        },
        username: {
            type: DataTypes.STRING(20),
            allowNull: false,
            unique: true,
            validate: {
                notEmpty: {
                    args: true,
                    msg: `Username is required`,
                },
                len: {
                    args: [3, 20],
                    msg: `Username must between 3 and 20 characters`,
                },
            },
        },
    },
    {
        timestamps: true,
        paranoid: true,
    }
    );

    Post.beforeCreate(async (post, options) => {
        post.username = post.username.toLowerCase();
    });

    Post.beforeUpdate(async (post, options) => {
        post.username = post.username.toLowerCase();
    });

    return Post;
    };

    /* Controller File */
    const db = require(`../config/db.config.jsx`);
    const postModel = db.postModel;

    const Sequelize = db.Sequelize;
    const sequelize = db.sequelize;
    const QueryTypes = db.QueryTypes;
    const DataTypes = db.DataTypes;
    const Op = db.Op;
    const ValidationErrorItem = db.ValidationErrorItem;
    const UniqueConstraintError = db.UniqueConstraintError;

    /* Create new Post */
    exports.create = async (req, res) => {
        const transactions = await sequelize.transaction();
        try {
            const trim = (noSpace) => {
                return noSpace.replace(/\s/g, ``);
            };
            const post = await postModel.create(
                {
                    title: req.body.title,
                    text: req.body.text,
                    username: trim(req.body.username),
            },
            { transaction: transactions }
        );
        await transactions.commit();
        res.status(200).json(post);
        } catch (err) {
            await transactions.rollback();
            const messages = {};
            let message;
            err.errors.forEach((error) => {
                messages[error.path] = error.message;
                message = messages[error.path];
            });
            res.status(500).json(message);
        }
    };

    /* Find All posts */
    exports.findAll = async (req, res) => {
        const transactions = await sequelize.transaction();
        try {
            const title = req.query.title;
            const text = req.query.text;
            const username = req.query.username;
            let finder = title ? { title: { [Op.like]: `%${title}%` } } : text ? { text: { [Op.like]: `%${text}%` } } : username ? { username: { [Op.like]: `%${username}%` } } : null;
            const posts = await postModel.findAll({
                as: `posts`,
                attributes: [`id`, `title`, `text`, `username`, `createdAt`, `updatedAt`, `deletedAt`],
                transaction: transactions,
                lock: false,
                paranoid: false,
                order: [[`id`, `DESC`]],
                where: finder,
            });
            await transactions.commit();
            res.status(200).json(posts);
        } catch (err) {
            await transactions.rollback();
            res.status(500).json(err.message);
        }
    };

    /* Router File */

    module.exports = (app) => {
        const router = require(`express`).Router();
        const postCtrl = require(`../controllers/post.controller.jsx`);

        router.route(`/post`).post(postCtrl.create).get(postCtrl.findAll);

        app.use(`/api/v1`, router);
    };

    /* MiddleWare Logger File */

    const moment = require(`moment`);

    /* Create Logger */
    const logger = (req, res, next) => {
        console.log(`${req.protocol}://${req.get(`host`)}${req.originalUrl} : ${moment().format()}`);
        next();
    };

    module.exports = logger;

    /* Server File */
    const express = require(`express`);
    const cors = require(`cors`);
    const logger = require(`./src/middleware/logger.jsx`);
    const app = express();

    const corsOptions = {
    origin: `http://localhost:4001`,
    optionsSuccessStatus: 200,
    };

    app
    .use(cors(corsOptions))
    .use(logger)
    .use(express.json())
    .use(express.urlencoded({ extended: false }))
    .get(`/`, (req, res) => res.status(200).send(`Welcome to fullstack tutorial application`));

    require(`./src/routes/routers.jsx`)(app);

    const PORT = process.env.PORT || 4000;
    app.listen(PORT, () => console.log(`Server is running on port ${PORT}...`));

输出结果运行良好，但主键自动递增仍在继续
网址：2022年8月28日星期一11：02：47+03：00执行（操作9）：开始交易;执行（操作编号12 d 76 f-d 7 dc-4040-9692- 3d 6 b853 feac 9）：插入posts（id、title、text、username、createdAt、updatedAt）值（默认值、？、？、？、？）;执行（操作编号12 d 76 f-d 7 dc-4040-9692- 3d 6 b853 feac 9）：回滚;