diff --git a/velox/exec/fuzzer/DuckQueryRunner.cpp b/velox/exec/fuzzer/DuckQueryRunner.cpp
index 1d9abc128373..cbf32e984483 100644
--- a/velox/exec/fuzzer/DuckQueryRunner.cpp
+++ b/velox/exec/fuzzer/DuckQueryRunner.cpp
@@ -462,6 +462,8 @@ std::optional<std::string> DuckQueryRunner::toSql(
   const auto& outputNames = joinNode->outputType()->names();
   std::stringstream sql;
 
+  sql << "SELECT " << folly::join(", ", outputNames);
+
   // Nested loop join without filter.
   VELOX_CHECK(
       joinNode->joinCondition() == nullptr,
diff --git a/velox/exec/fuzzer/PrestoQueryRunner.cpp b/velox/exec/fuzzer/PrestoQueryRunner.cpp
index 143cd18cfb0f..3e471321eba8 100644
--- a/velox/exec/fuzzer/PrestoQueryRunner.cpp
+++ b/velox/exec/fuzzer/PrestoQueryRunner.cpp
@@ -676,6 +676,8 @@ std::optional<std::string> PrestoQueryRunner::toSql(
   const auto& outputNames = joinNode->outputType()->names();
   std::stringstream sql;
 
+  sql << "SELECT " << folly::join(", ", outputNames);
+
   // Nested loop join without filter.
   VELOX_CHECK(
       joinNode->joinCondition() == nullptr,