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docs: improve schema evolution api examples (#1929)

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This commit is contained in:
QianZhu
2024-12-12 10:52:06 -08:00
committed by GitHub
parent 17e4022045
commit c0ee370f83
3 changed files with 24 additions and 6 deletions
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10
docs/src/guides/tables.md
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@@ -804,12 +804,13 @@ a table:
You can add new columns to the table with the `add_columns` method. New columns
are filled with values based on a SQL expression. For example, you can add a new
column `y` to the table and fill it with the value of `x + 1`.
column `y` to the table, fill it with the value of `x * 2` and set the expected
data type for it.
=== "Python"
```python
table.add_columns({"double_price": "price * 2"})
--8<-- "python/python/tests/docs/test_basic.py:add_columns"
```
**API Reference:** [lancedb.table.Table.add_columns][]
@@ -849,8 +850,7 @@ rewriting the column, which can be a heavy operation.
```python
import pyarrow as pa
table.alter_column({"path": "double_price", "rename": "dbl_price",
"data_type": pa.float32(), "nullable": False})
--8<-- "python/python/tests/docs/test_basic.py:alter_columns"
```
**API Reference:** [lancedb.table.Table.alter_columns][]
@@ -873,7 +873,7 @@ will remove the column from the schema.
=== "Python"
```python
table.drop_columns(["dbl_price"])
--8<-- "python/python/tests/docs/test_basic.py:drop_columns"
```
**API Reference:** [lancedb.table.Table.drop_columns][]

4
nodejs/examples/basic.test.ts
View File

@@ -119,7 +119,9 @@ test("basic table examples", async () => {
{
// --8<-- [start:add_columns]
await tbl.addColumns([{ name: "double_price", valueSql: "price * 2" }]);
await tbl.addColumns([
{ name: "double_price", valueSql: "cast((price * 2) as Float)" },
]);
// --8<-- [end:add_columns]
// --8<-- [start:alter_columns]
await tbl.alterColumns([

16
python/python/tests/docs/test_basic.py
View File

@@ -75,6 +75,22 @@ def test_quickstart():
for _ in range(1000)
]
)
# --8<-- [start:add_columns]
tbl.add_columns({"double_price": "cast((price * 2) as float)"})
# --8<-- [end:add_columns]
# --8<-- [start:alter_columns]
tbl.alter_columns(
{
"path": "double_price",
"rename": "dbl_price",
"data_type": pa.float64(),
"nullable": True,
}
)
# --8<-- [end:alter_columns]
# --8<-- [start:drop_columns]
tbl.drop_columns(["dbl_price"])
# --8<-- [end:drop_columns]
# --8<-- [start:create_index]
# Synchronous client
tbl.create_index(num_sub_vectors=1)