[TOC] ### 字段自增 ``` const flow = await this.ctx.model.Flow.findOne({ where: { art_id } }); await flow.increment('index', { by: 900 }); ``` ### 字段自减 ``` const flow = await this.ctx.model.Flow.findOne({ where: { art_id } }); await flow.decrement('index', { by: 900 }); ```