adding explain_only option for aurora run workload

run_cost_model.py

@@ -177,6 +177,7 @@ def parse_queries_wrapper(
     parser.add_argument("--save_best", action="store_true")
     parser.add_argument("--train_model", action="store_true")
     parser.add_argument("--is_query", action="store_true")
+    parser.add_argument("--explain_only", action="store_true")
     parser.add_argument("--plan_featurization", default="AuroraEstSystemCardDetail")
     parser.add_argument(
         "--hyperparameter_path",
@@ -315,6 +316,7 @@ def parse_queries_wrapper(
             rank=args.run_workload_rank,
             world_size=args.run_workload_world_size,
             s3_output_path=args.s3_output_path,
+            explain_only=args.explain_only
         )
 
     if args.parse_plans:

workloads/cross_db_benchmark/benchmark_tools/aurora/run_workload.py

@@ -81,6 +81,7 @@ def run_aurora_workload(
     cap_workload,
     rank,
     world_size,
+    explain_only
 ):
     os.makedirs(os.path.dirname(target_path), exist_ok=True)
 
@@ -136,7 +137,7 @@ def run_aurora_workload(
 
         hint = hint_list[i]
         curr_statistics = db_conn.run_query_collect_statistics(
-            sql_query, repetitions=repetitions_per_query, prefix=hint
+            sql_query, repetitions=repetitions_per_query, prefix=hint, explain_only=explain_only
         )
         curr_statistics.update(sql=sql_query)
         curr_statistics.update(hint=hint)

workloads/cross_db_benchmark/benchmark_tools/run_workload.py

@@ -35,6 +35,7 @@ def run_workload(
     world_size=1,
     # Used by Athena
     s3_output_path=None,
+    explain_only=False
 ):
     if database == DatabaseSystem.POSTGRES:
         run_pg_workload(
@@ -71,6 +72,7 @@ def run_workload(
                 cap_workload=cap_workload,
                 rank=rank,
                 world_size=world_size,
+                explain_only=explain_only
             )
     elif database == DatabaseSystem.REDSHIFT:
         run_redshift_workload(