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Lai Zhou commented on CALCITE-2973: ----------------------------------- [~julianhyde] , consider another query that the join conditions contains an equi condition and a non-equi condition meanwhile : {code:java} SELECT t1.i_item_desc FROM item t1 LEFT OUTER JOIN item_1 t2 ON t1.i_item_sk=t2.i_item_sk and t2.i_item_sk <10000{code} Merge join is also good for this query. But now it will be converted to a nested loop join. > Make EnumerableMergeJoinRule to support a theta join > ---------------------------------------------------- > > Key: CALCITE-2973 > URL: https://issues.apache.org/jira/browse/CALCITE-2973 > Project: Calcite > Issue Type: New Feature > Components: core > Affects Versions: 1.19.0 > Reporter: Lai Zhou > Priority: Minor > > Now the EnumerableMergeJoinRule only supports an inner and equi join. > If users make a theta-join query for a large dataset (such as 10000*10000), > the nested-loop join process will take dozens of time than the sort-merge > join process . > So if we can apply merge-join or hash-join rule for a theta join, it will > improve the performance greatly. -- This message was sent by Atlassian JIRA (v7.6.3#76005)