我有一个名为Transactions的表,其中包含以下模式:
ID | P_Name | O_ID | P_ID | P_Qty |
===============================================
1 | PRODUCT A | 1 | 140 | 100 |
2 | PRODUCT A | 1 | 140 | 15 |
3 | PRODUCT B | 1 | 130 | 10 |
4 | PRODUCT C | 1 | 120 | 2 |
我想总结所有共享P_Name的P_Qty,这样我最终可以得到:
P_Name | P_ID | P_Qty |
===============================
PRODUCT A | 140 | 115 |
PRODUCT B | 130 | 10 |
PRODUCT C | 120 | 2 |
正如您所看到的,P_Qty是P_ID相同的总和,我使用的是ContentResolver,如下所示,但是如图所示失败:
String selection = null;
String[] selectionArgs = null;
String orderBy = TRANSACTION_PRODUCT_NAME + " ASC";
Cursor cursor = getActivity().getContentResolver().query(
SalesManContract.TRANSACTION_CONTENT_URI,
new String[] {TRANSACTION_PRODUCT_NAME," SUM(P_Qty) AS
P_Qty"},
selection,
selectionArgs,
orderBy);
结果是:
P_Name | P_ID | P_Qty |
===============================
PRODUCT A | 140 | 127 |
如何使用ContentResolver实现我想要的结果