fix(node): accept exist_ok in createTable (#4432)

TypeScript CreateTableOptions.mode omitted exist_ok even though
createTable already forwards that mode to the native client.

closes: #2900

---------

Co-authored-by: Preston Zhao <195942578+canyang25@users.noreply.github.com>

docs/src/js/interfaces/CreateTableOptions.md

@@ -65,7 +65,7 @@ then no error will be raised.
 ### mode
 
 ```ts
-mode: "overwrite" | "create";
+mode: "overwrite" | "create" | "exist_ok";
 ```
 
 The mode to use when creating the table.
@@ -76,6 +76,9 @@ happen.  Any provided data will be ignored.
 
 If this is set to "overwrite" then any existing table will be replaced.
 
+If this is set to "exist_ok" then an existing table is opened and any
+provided data is ignored.
+
 ***
 
 ### schema?

nodejs/__test__/connection.test.ts

@@ -117,6 +117,20 @@ describe("given a connection", () => {
     await expect(tbl.countRows()).resolves.toBe(1);
   });
 
+  it("should keep the existing table when mode is exist_ok", async () => {
+    const created = await db.createTable("test", [{ id: 1 }, { id: 2 }], {
+      mode: "exist_ok",
+    });
+    await expect(created.countRows()).resolves.toBe(2);
+
+    const reopened = await db.createTable("test", [{ id: 9 }], {
+      mode: "exist_ok",
+    });
+    await expect(reopened.countRows()).resolves.toBe(2);
+    const rows = (await reopened.query().toArray()) as { id: number }[];
+    expect(rows.map((row) => row.id).sort()).toEqual([1, 2]);
+  });
+
   it("should respect limit and page token when listing tables", async () => {
     const db = await connect(tmpDir.name);
 

nodejs/lancedb/connection.ts

@@ -53,8 +53,11 @@ export interface CreateTableOptions {
    * happen.  Any provided data will be ignored.
    *
    * If this is set to "overwrite" then any existing table will be replaced.
+   *
+   * If this is set to "exist_ok" then an existing table is opened and any
+   * provided data is ignored.
    */
-  mode: "create" | "overwrite";
+  mode: "create" | "overwrite" | "exist_ok";
   /**
    * If this is true and the table already exists and the mode is "create"
    * then no error will be raised.