> For the complete documentation index, see [llms.txt](https://kythuat.dtechvn.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kythuat.dtechvn.com/effect/kiem-tra-du-lieu.md).

# KIỂM TRA DỮ LIỆU

## 1. Kiểm tra nghiệp vụ có nhập nhiều ma\_kh không

```sql
/*
- nghiệp vụ có cột ma_kh ở dưới lưới dữ liệu
- kiểm tra xem có nhập nhiều ma_kh ở nghiệp vụ không
*/
-- kiểm tra khachhang trên 1 phiếu
select ngay_thc,chung_tu,count(*)
from
(
select ngay_thc,chung_tu, ma_kh
from _thu_tien where ma_scr=706
group by ngay_thc,chung_tu, ma_kh
) T group by ngay_thc,chung_tu
having count(*)>1
order by ngay_thc desc
```


---

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