support for single repartition join mode

src/test/regress/citus_tests/query_generator/README.md

@@ -89,6 +89,8 @@ Schema for Query configuration:
 ```yaml
 queryCount: <int>
 queryOutFile: <string>
+repartitionJoin: <bool>
+singleRepartitionJoin: <bool>
 semiAntiJoin: <bool>
 cartesianProduct: <bool>
 limit: <bool>
@@ -116,6 +118,8 @@ Explanation:
 ```yaml
 queryCount: "number of queries to generate"
 queryOutFile: "file to write generated queries"
+repartitionJoin: "should we enable repartition join"
+singleRepartitionJoin: "should we make default repartition join mode as single repartition join (default is dual)"
 semiAntiJoin: "should we support semi joins (WHERE col IN (Subquery))"
 cartesianProduct: "should we support cartesian joins"
 limit: "should we support limit clause"

src/test/regress/citus_tests/query_generator/config/config.py

@@ -28,6 +28,8 @@ class Config:
         self.targetRteCount = configObj["targetRteCount"]
         self.targetCteCount = configObj["targetCteCount"]
         self.targetCteRteCount = configObj["targetCteRteCount"]
+        self.repartitionJoin = configObj["repartitionJoin"]
+        self.singleRepartitionJoin = configObj["singleRepartitionJoin"]
         self.semiAntiJoin = configObj["semiAntiJoin"]
         self.cartesianProduct = configObj["cartesianProduct"]
         self.limit = configObj["limit"]

src/test/regress/citus_tests/query_generator/config/config.yaml

@@ -2,6 +2,8 @@ interactiveMode: false
 queryCount: 250
 queryOutFile: queries.sql
 ddlOutFile: ddls.sql
+repartitionJoin: true
+singleRepartitionJoin: false
 semiAntiJoin: true
 cartesianProduct: false
 limit: true

src/test/regress/citus_tests/query_generator/generate_queries.py

@@ -55,8 +55,15 @@ def _fileMode(ddls, data):
     )
     with open(fileName, "w") as f:
         # enable repartition joins due to https://github.com/citusdata/citus/issues/6865
+        queryLines = []
+        if getConfig().repartitionJoin:
             enableRepartitionJoinCommand = "SET citus.enable_repartition_joins TO on;\n"
-        queryLines = [enableRepartitionJoinCommand]
+            queryLines.append(enableRepartitionJoinCommand)
+        if getConfig().singleRepartitionJoin:
+            singleRepartitionJoinCommand = (
+                "SET citus.enable_single_hash_repartition_joins TO on;\n"
+            )
+            queryLines.append(singleRepartitionJoinCommand)
         queryId = 1
         for _ in range(queryCount):
             query = newQuery()