feat: add drop_index() method (#2039)

Closes #1665

python/python/lancedb/table.py

@@ -586,6 +586,26 @@ class Table(ABC):
         """
         raise NotImplementedError
 
+    def drop_index(self, name: str) -> None:
+        """
+        Drop an index from the table.
+
+        Parameters
+        ----------
+        name: str
+            The name of the index to drop.
+
+        Notes
+        -----
+        This does not delete the index from disk, it just removes it from the table.
+        To delete the index, run [optimize][lancedb.table.Table.optimize]
+        after dropping the index.
+
+        Use [list_indices][lancedb.table.Table.list_indices] to find the names of
+        the indices.
+        """
+        raise NotImplementedError
+
     @abstractmethod
     def create_scalar_index(
         self,
@@ -1594,6 +1614,9 @@ class LanceTable(Table):
             )
         )
 
+    def drop_index(self, name: str) -> None:
+        return LOOP.run(self._table.drop_index(name))
+
     def create_scalar_index(
         self,
         column: str,
@@ -2716,6 +2739,26 @@ class AsyncTable:
                 add_note(e, help_msg)
             raise e
 
+    async def drop_index(self, name: str) -> None:
+        """
+        Drop an index from the table.
+
+        Parameters
+        ----------
+        name: str
+            The name of the index to drop.
+
+        Notes
+        -----
+        This does not delete the index from disk, it just removes it from the table.
+        To delete the index, run [optimize][lancedb.table.AsyncTable.optimize]
+        after dropping the index.
+
+        Use [list_indices][lancedb.table.AsyncTable.list_indices] to find the names
+        of the indices.
+        """
+        await self._inner.drop_index(name)
+
     async def add(
         self,
         data: DATA,

python/python/tests/test_index.py

@@ -80,6 +80,10 @@ async def test_create_scalar_index(some_table: AsyncTable):
     # can also specify index type
     await some_table.create_index("id", config=BTree())
 
+    await some_table.drop_index("id_idx")
+    indices = await some_table.list_indices()
+    assert len(indices) == 0
+
 
 @pytest.mark.asyncio
 async def test_create_bitmap_index(some_table: AsyncTable):

python/python/tests/test_table.py

@@ -1008,6 +1008,10 @@ def test_create_scalar_index(mem_db: DBConnection):
     results = table.search([5, 5]).where("x != 'b'").to_arrow()
     assert results["_distance"][0].as_py() > 0
 
+    table.drop_index(scalar_index.name)
+    indices = table.list_indices()
+    assert len(indices) == 0
+
 
 def test_empty_query(mem_db: DBConnection):
     table = mem_db.create_table(

python/src/table.rs

@@ -194,6 +194,14 @@ impl Table {
         })
     }
 
+    pub fn drop_index(self_: PyRef<'_, Self>, index_name: String) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.inner_ref()?.clone();
+        future_into_py(self_.py(), async move {
+            inner.drop_index(&index_name).await.infer_error()?;
+            Ok(())
+        })
+    }
+
     pub fn list_indices(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
         let inner = self_.inner_ref()?.clone();
         future_into_py(self_.py(), async move {