MP中的字段还可以利用函数来查询拼接sql

 //根据value查询
    @GetMapping("getTest")
    public List<HashMap> getTest() {
        QueryWrapper<TTest> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("substr(name,1,2)","99999");
        List<TTest> list1 = testService.list(queryWrapper);
        List<HashMap> list = dictService.getTest();
        return list;
    }