diff --git a/devTools/docker/refresh-grapher-data.sh b/devTools/docker/refresh-grapher-data.sh
index 4f954f1890a..c00f37f285a 100755
--- a/devTools/docker/refresh-grapher-data.sh
+++ b/devTools/docker/refresh-grapher-data.sh
@@ -12,7 +12,11 @@ set -x
 : "${DATA_FOLDER:?Need to set DATA_FOLDER non-empty}"
 
 _mysql() {
-    mysql --default-character-set=utf8mb4 -h"$GRAPHER_DB_HOST" -u"$GRAPHER_DB_USER" -p"$GRAPHER_DB_PASS" -P "${GRAPHER_DB_PORT}" "$@"
+    if [ -z "$GRAPHER_DB_PASS" ]; then
+        mysql --default-character-set=utf8mb4 -h"$GRAPHER_DB_HOST" -u"$GRAPHER_DB_USER" -P "${GRAPHER_DB_PORT}" "$@"
+    else
+        mysql --default-character-set=utf8mb4 -h"$GRAPHER_DB_HOST" -u"$GRAPHER_DB_USER" -p"$GRAPHER_DB_PASS" -P "${GRAPHER_DB_PORT}" "$@"
+    fi
 }
 
 import_db() {