Sorry, there is something wrong with the above email format.You could check it out below Hi community,
Now I am reading the source code of calcite sql hint,and I found in SubTreeHintPropagateShuttle class, from the root node, it will be the most search 3 layers down child nodes, trying to propagate the original RelNode hints, 3 are fixed. SubTreeHintPropagateShuttle is a RelShuttle,and its purpose is that when a rule rewrited a RelNode Tree, need to propagate the original RelNode Hints to rewrite RelNode. More details could see RelOptUtil# propagateRelHints method. My idea is that make SubTreeHintPropagateShuttle search child layers could let user configurable. One way is to add the setHintSearchNum and getHintSearchNum methods to the RelOptCluster class, and then in the RelOptUtil#propagateRelHints method, using originalRel.getCluster().getHintSearchNum to get the search the number of layers, and then transfer to SubTreeHintPropagateShuttle.This is just my idea, not the final implementation. Code links: 1. https://github.com/apache/calcite/blob/50c3edfc3d6630528ab51fe836bd50df82cc7db8/core/src/main/java/org/apache/calcite/plan/RelOptUtil.java#L4199C7-L4202C8 2. https://github.com/apache/calcite/blob/50c3edfc3d6630528ab51fe836bd50df82cc7db8/core/src/main/java/org/apache/calcite/plan/RelOptUtil.java#L426C2-L435C34 Best, LakeShen LakeShen <[email protected]> 于2023年8月14日周一 11:47写道： > Hi community, Now I am reading the source code of calcite sql hint,and I > found in SubTreeHintPropagateShuttle class, from the root node, it will be > the most search 3 layers down child nodes, trying to propagate > the original RelNode hints, 3 are fixed. SubTreeHintPropagateShuttle is a > RelShuttle,and its purpose is that when a rule rewrited a RelNode Tree, > need to propagate the original RelNode Hints to rewrite RelNode. More > details could see RelOptUtil# propagateRelHints method. My idea is that > make SubTreeHintPropagateShuttle search child layers could let user > configurable. One way is to add the setHintSearchNum and getHintSearchNum > methods to the RelOptCluster class, and then in the > RelOptUtil#propagateRelHints method, using > originalRel.getCluster().getHintSearchNum > to get the search the number of layers, and then transfer to > SubTreeHintPropagateShuttle.This is just my idea, not the final > implementation. Code links: 1. > https://github.com/apache/calcite/blob/50c3edfc3d6630528ab51fe836bd50df82cc7db8/core/src/main/java/org/apache/calcite/plan/RelOptUtil.java#L4199C7-L4202C8 > 2. > https://github.com/apache/calcite/blob/50c3edfc3d6630528ab51fe836bd50df82cc7db8/core/src/main/java/org/apache/calcite/plan/RelOptUtil.java#L426C2-L435C34 > > Best, > LakeShen >
