sabz90 commented on issue #7703:
URL: https://github.com/apache/shardingsphere/issues/7703#issuecomment-737068772


   > @strongduanmu Thank you for diving into it. @tristaZero My apologies that 
the proposed solution may not work as I originally agreed. The where clause 
doesn't contain the sharding key.
   > 
   > e.g. `update ACCOUNT_INFO set name=??, account_id=??, zip=??, version=?? 
where id = ??` was the generated sql with account_id being the sharding key. 
The `shardingValue` is empty in the code @strongduanmu posted 
(ShardingUpdateStatementValidator.java).
   > 
   > 
![image](https://user-images.githubusercontent.com/3125184/100831541-d7d84100-341a-11eb-85d8-3336a726d57e.png)
   > 
   > So the logic may be
   > 
   > ```
   > if (no shardingKey in SET Clause)
   >     then PASS
   > else if (no shardingKey in WHERE Clause)
   >     then append sharding column and value to WHERE Clause
   > else if (the value of shardingKey in SET Clause == the value of 
shardingKey in WHERE Clause)
   >     then PASS
   > else
   >     then an exception
   > ```
   
   The second condition will fix this issue but it is a risky option - we are 
just assuming that the user did not intend to put the sharding column in the 
where clause. 
   
   ```
   else if (no shardingKey in WHERE Clause)
       then append sharding column and value to WHERE Clause
   ```
   
   So a safer option would be to define an Annotation, something like 
"@ForceWhereClause" which should then indicate to sharding-sphere that it has 
to use the value from SET clause and put in a where clause along in the final 
statement.
   
   For now i have solved the problem by using CompositeKey @IdClass method , 
which makes hibernate include the column in where clause, but it's more of a 
hack since the sharding column is not really a composite key in the database 
level.


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