diff --git a/cli/test.sh b/cli/test.sh
index d26f7ba4..f4e4e3f1 100755
--- a/cli/test.sh
+++ b/cli/test.sh
@@ -32,7 +32,7 @@ case $TEST_HANDLER in
 	;;
 "http")
 	echo "==> Testing REST API handler"
-	export BENDSQL_DSN="databend+http://${DATABEND_USER}:${DATABEND_PASSWORD}@${DATABEND_HOST}:8000/?sslmode=disable&presign=on&format_null_as_str=0"
+	export BENDSQL_DSN="databend+http://${DATABEND_USER}:${DATABEND_PASSWORD}@${DATABEND_HOST}:8000/?sslmode=disable&presign=on"
 	;;
 *)
 	echo "Usage: $0 [flight|http]"
diff --git a/tests/Makefile b/tests/Makefile
index 1b98703c..3b061853 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -15,7 +15,7 @@ test-core: up
 
 test-driver: up
 	cargo test --test driver
-	TEST_DATABEND_DSN=databend+flight://root:@localhost:8900/default?sslmode=disable&format_null_as_str=0 cargo test --features flight-sql --test driver
+	TEST_DATABEND_DSN=databend+flight://root:@localhost:8900/default?sslmode=disable cargo test --features flight-sql --test driver
 
 test-bendsql: up
 	cd .. && ./cli/test.sh http