[GitHub] [incubator-shardingsphere] wy-coder edited a comment on issue #2910: Use data source ID and table ID to force routing is required. There is no Value in some situation.

[GitBox <gi...@apache.org>]

wy-coder edited a comment on issue #2910: Use data source ID and table ID to force routing is required. There is no Value in some situation. 
URL: https://github.com/apache/incubator-shardingsphere/issues/2910#issuecomment-524198221
 
 
   Forced routing has a function that needs to be implemented, that is, sending SQL to the sub-table specified by the specified data source for execution.
   
   And forced routing should not only take effect in the table that specifies the HintShardingStrategy.
   
   For example：
   ```
    SELECT
   	MIN(KEY_FIELD) START_KEY,
   	MAX(KEY_FIELD) END_KEY,
   	count(1) ROW_COUNT
   FROM
   	(
   		SELECT
   			KEY_FIELD ,@rownum:=@rownum + 1 AS rownum
   	
   FROM
   	(select client_key as KEY_FIELD from **cif_client** where 1=1) t1,
   	(SELECT @rownum := - 1) t
   ORDER BY
   	t1.key_field
   ) tt
   GROUP BY
   	floor(tt.rownum / 200000)
   
   ```
   This is a paging SQL. I need to first cut a table into 200,000 rows as a segment. Then distribute this segment to a batch executor for processing.
   
   ```
   
           HintManager hintManager = HintManager.getInstance();
           hintManager.addDatabaseShardingValue(tableName,value);  **//value?!!!Where did I get the value?!!**  I already have data source name (or ID) and table name (or ID)!!
           hintManager.addTableShardingValue(tableName,value);  **//value?!!!Where did I get the value?!!**
   
   ```
   
   ```
           TableRuleConfiguration result = new TableRuleConfiguration();
           result.setLogicTable(tableName);
           result.setActualDataNodes("ds_${0..2}."+tableName+"_${0..2}");
           result.setDatabaseShardingStrategyConfig(new StandardShardingStrategyConfiguration("client_no",new CifDatabaseShardingAlgorithm()));
   // I just want to execute paging statements in hint, but i must modify the Strategy of this table? what??!!!
           result.setTableShardingStrategyConfig(new StandardShardingStrategyConfiguration("client_no",new CifTableShardingAlgorithm()));
          
   ```
   
   
   
   
   

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