diff --git a/test.sh b/test.sh
index 8c9ed4d..0463b04 100755
--- a/test.sh
+++ b/test.sh
@@ -51,7 +51,7 @@ test_run() {
         banner '*' "Standard automatic upgrade of PostgreSQL from version ${VERSION} to ${TARGET} SUCCEEDED!"
     fi
 
-    # Shut down containers from previous test runs
+    # Shut down any containers that are still running
     docker compose -f docker-compose-pgauto.yml down
 
     ##
@@ -65,6 +65,21 @@ test_run() {
     # Create the PostgreSQL database using a specific version of PostgreSQL
     docker compose -f "docker-compose-pg${VERSION}.yml" run --rm --remove-orphans server create_db
 
+    # Run the PostgreSQL container in one shot mode
+    TARGET_TAG="${TARGET}-${FLAVOR}" docker compose -f docker-compose-pgauto.yml run --rm --remove-orphans \
+        -e PGAUTO_ONESHOT=yes postgres
+
+    # Verify the PostgreSQL data files are now the target version
+    PGVER=$(sudo cat postgres-data/PG_VERSION)
+    if [ "$PGVER" != "${TARGET}" ]; then
+        banner '*' "'One shot' automatic upgrade of PostgreSQL from version ${VERSION} to ${TARGET} FAILED!"
+        FAILURE=1
+    else
+        banner '*' "'One shot' automatic upgrade of PostgreSQL from version ${VERSION} to ${TARGET} SUCCEEDED!"
+    fi
+
+    # Shut down any containers that are still running
+    docker compose -f docker-compose-pgauto.yml down
 
     # If running on CI, delete the Postgres Docker image to avoid space problems
     if [ -n "$CI" ]; then