wehub-resource-sync
89 lines
1.7 KiB
Markdown
89 lines
1.7 KiB
Markdown
# `Table::update` and `Table::remove`
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Once a `Table` has been created, it can be updated with new data conforming to
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the `Table`'s schema. `Table::update` supports the same data formats as
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`Client::table`, minus _schema_.
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<div class="javascript">
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```javascript
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const schema = {
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a: "integer",
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b: "float",
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};
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const table = await perspective.table(schema);
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table.update(new_data);
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```
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</div>
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<div class="python">
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```python
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schema = {"a": "integer", "b": "float"}
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table = perspective.Table(schema)
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table.update(new_data)
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```
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</div>
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Without an `index` set, calls to `update()` _append_ new data to the end of the
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`Table`. Otherwise, Perspective allows
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[_partial updates_ (in-place)](#index-and-limit) using the `index` to determine
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which rows to update:
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<div class="javascript">
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```javascript
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indexed_table.update({ id: [1, 4], name: ["x", "y"] });
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```
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</div>
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<div class="python">
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```python
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indexed_table.update({"id": [1, 4], "name": ["x", "y"]})
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```
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</div>
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Any value on a `Client::table` can be unset using the value `null` in JSON or
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Arrow input formats. Values may be unset on construction, as any `null` in the
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dataset will be treated as an unset value. `Table::update` calls do not need to
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provide _all columns_ in the `Table`'s schema; missing columns will be omitted
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from the `Table`'s updated rows.
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<div class="javascript">
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```javascript
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table.update([{ x: 3, y: null }]); // `z` missing
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```
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</div>
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<div class="python">
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```python
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table.update([{"x": 3, "y": None}]) # `z` missing
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```
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</div>
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Rows can also be removed from an indexed `Table`, by calling `Table::remove`
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with an array of index values:
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<div class="javascript">
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```javascript
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indexed_table.remove([1, 4]);
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```
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</div>
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<div class="python">
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```python
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indexed_table.remove([1, 4])
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```
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</div>
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