michaelsembwever commented on code in PR #24567:
URL: https://github.com/apache/datafusion/pull/24567#discussion_r4057918814
##########
docs/source/user-guide/sql/dml.md:
##########
@@ -136,3 +136,114 @@ INSERT INTO <i><b>table_name</i></b> { VALUES (
<i><b>expression</i></b> [, ...]
| 2 |
+-------+
```
+
+## DELETE
+
+Removes rows from a table.
+
+<pre>
+DELETE FROM <i><b>table_name</b></i> [ WHERE <i><b>condition</b></i> ]
+</pre>
+
+`DELETE` returns the number of removed rows in a column named `count`.
+
+If you omit the `WHERE` clause, DataFusion removes all rows.
+
+DataFusion removes a row only if the condition is true for that row. SQL
three-valued logic applies: if the condition evaluates to `NULL`, the row
remains. For example, `WHERE value > 15` keeps a row with a `NULL` value,
because `NULL > 15` is `NULL`.
+
+Not all tables support `DELETE`. See [Table support for DELETE and
UPDATE](#table-support-for-delete-and-update).
+
+### Examples
+
+Remove the rows that match a condition:
+
+```sql
+> DELETE FROM target_table WHERE id > 1;
++-------+
+| count |
++-------+
+| 2 |
++-------+
+```
+
+Remove all rows:
+
+```sql
+> DELETE FROM target_table;
++-------+
+| count |
++-------+
+| 3 |
++-------+
+```
+
+## UPDATE
+
+Changes the values of existing rows.
+
+<pre>
+UPDATE <i><b>table_name</b></i> SET <i><b>column</b></i> =
<i><b>expression</b></i> [, ...] [ WHERE <i><b>condition</b></i> ]
+</pre>
+
+`UPDATE` returns the number of affected rows in a column named `count`.
+
+If you omit the `WHERE` clause, DataFusion changes all rows. The three-valued
logic of `DELETE` also applies here.
+
+Each assignment expression reads the row values from before the statement.
`SET a = b, b = a` therefore exchanges the two values.
+
+Not all tables support `UPDATE`. See [Table support for DELETE and
UPDATE](#table-support-for-delete-and-update).
+
+### Examples
+
+Set one column in the rows that match a condition:
+
+```sql
+> UPDATE target_table SET name = 'Baz' WHERE id = 2;
++-------+
+| count |
++-------+
+| 1 |
++-------+
+```
+
+Set two columns, one from an expression:
+
+```sql
+> UPDATE target_table SET value = value * 2, name = 'Doubled' WHERE id < 3;
++-------+
+| count |
++-------+
+| 2 |
++-------+
+```
+
+## Table support for DELETE and UPDATE
+
+The table provider does the work for `DELETE` and `UPDATE`. Support is
therefore a property of each table:
+
+- `CREATE TABLE` makes an in-memory table. In-memory tables support both
statements.
+- `CREATE EXTERNAL TABLE` makes a file-based table. File-based tables support
neither statement.
+- Views support neither statement.
+- A custom table provider supports a statement only if it implements the
matching hook. See [Custom Table
Provider](../../library-user-guide/custom-table-providers.md#row-level-dml-delete-and-update).
+
+A table that gives no support returns an error:
+
+```text
+DELETE operation on table 'my_external_table'
+caused by
+This feature is not implemented: DELETE not supported for Base table
+```
+
+### Limitations
+
+:::{warning}
Review Comment:
done
https://github.com/apache/datafusion/pull/24567/changes/e4f2a13d8d4e184e4248af6882aa65464bc0c71e
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