kimmking commented on issue #4580: shardingsphere: Regarding routing to multiple data nodes, when querying with aggregate functions (count, max, avg ...), how to deal with the total statistics of multiple tables? URL: https://github.com/apache/incubator-shardingsphere/issues/4580#issuecomment-594024605 Group query/aggregation is supported by ShardingSphere. In version 4.x, you can config precise algorithm for between statements. > We need to discuss this pull request: > 1. For standard sharding strategy, user need config precise algorithm (for =, IN) and range algorithm (for BETWEEN AND, <, >, >=, <=). If range algorithm absent, the SQL contains BETWEEN should query all data nodes. That is correct, because user know they do not config range algorithm explicitly; > 2. For inline sharding strategy, user only can config precise algorithm via inline expression, and cannot config range algorithm. So throw exception when SQL contains BETWEEN may better than query all data nodes. If query all data nodes instead of explicit exception, user may missing the potential performance issue. In version 5.x of master branch(not release yet), you can directly config the follow parameter in server.yaml to allow between statement query in inline sharding. > allow.range.query.with.inline.sharding: true
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