fix(editor): apply default transaction mode when binding unbound tabs

apps/desktop/src/stores/__tests__/queryStore.defaultTransactionMode.spec.ts

@@ -102,4 +102,34 @@ describe("queryStore default transaction mode", () => {
     const tab = store.tabs.find((item) => item.id === tabId)!;
     expect(tab.autoCommit).toBe(true);
   });
+
+  it("applies the manual default when an unbound file tab binds to a transactional connection", async () => {
+    editorSettings.defaultTransactionMode = "manual";
+    mocks.getConnectionConfig.mockImplementation((connectionId: string) => (connectionId === "mysql-1" ? { id: "mysql-1", name: "MySQL", db_type: "mysql", database: "app" } : undefined));
+
+    const { useQueryStore } = await import("@/stores/queryStore");
+    const store = useQueryStore();
+    // Externally opened SQL files and saved-SQL tabs start unbound
+    // (connectionId ""), so their initial mode falls back to auto-commit.
+    const tabId = store.createTab("", "", "Query", "query");
+    expect(store.tabs.find((item) => item.id === tabId)!.autoCommit).toBe(true);
+
+    store.updateConnection(tabId, "mysql-1", "app");
+
+    expect(store.tabs.find((item) => item.id === tabId)!.autoCommit).toBe(false);
+  });
+
+  it("keeps the manual default when switching between transactional connections", async () => {
+    editorSettings.defaultTransactionMode = "manual";
+    mocks.getConnectionConfig.mockImplementation((connectionId: string) => (connectionId === "mysql-1" ? { id: "mysql-1", name: "MySQL", db_type: "mysql", database: "app" } : { id: "oracle-1", name: "Oracle", db_type: "oracle", database: "ORCL" }));
+
+    const { useQueryStore } = await import("@/stores/queryStore");
+    const store = useQueryStore();
+    const tabId = store.createTab("oracle-1", "ORCL", "Query", "query", "APP");
+    expect(store.tabs.find((item) => item.id === tabId)!.autoCommit).toBe(false);
+
+    store.updateConnection(tabId, "mysql-1", "app");
+
+    expect(store.tabs.find((item) => item.id === tabId)!.autoCommit).toBe(false);
+  });
 });

apps/desktop/src/stores/queryStore.ts

@@ -4261,10 +4261,14 @@ export const useQueryStore = defineStore("query", () => {
     if (tab.oracleTxnPossiblyDirty !== undefined) tab.oracleTxnPossiblyDirty = false;
   }
 
-  function rollbackTabTransaction(tab: QueryTab, options?: { resetAutoCommit?: boolean }) {
+  function rollbackTabTransaction(tab: QueryTab, options?: { resetAutoCommit?: boolean; resetAutoCommitDbType?: string }) {
     if (tab.txnSessionId) void rollbackTransaction(tab.id);
     if (options?.resetAutoCommit) {
-      const dbType = useConnectionStore().getConfig(tab.connectionId)?.db_type;
+      // Callers switching a tab to another connection pass the target db type
+      // explicitly: the tab still carries the previous connectionId at reset
+      // time, and unbound file/saved-SQL tabs have none at all (which would
+      // force auto-commit even when the default mode is manual, #8863).
+      const dbType = options.resetAutoCommitDbType ?? useConnectionStore().getConfig(tab.connectionId)?.db_type;
       tab.autoCommit = defaultAutoCommitForDbTypeWithSetting(dbType);
     }
     clearOracleTxnPossiblyDirty(tab);
@@ -4608,7 +4612,7 @@ export const useQueryStore = defineStore("query", () => {
   function updateConnection(id: string, connectionId: string, database = "", options: UpdateExecutionTargetOptions = {}) {
     const tab = tabs.value.find((t) => t.id === id);
     if (!tab || tab.connectionId === connectionId) return;
-    rollbackTabTransaction(tab, { resetAutoCommit: true });
+    rollbackTabTransaction(tab, { resetAutoCommit: true, resetAutoCommitDbType: useConnectionStore().getConfig(connectionId)?.db_type });
     void closeResultSession(tab);
     void closeClientConnectionSession(tab);
     tab.connectionId = connectionId;