jackye1995 commented on a change in pull request #3375:
URL: https://github.com/apache/iceberg/pull/3375#discussion_r743125680
##########
File path: site/docs/spark-procedures.md
##########
@@ -240,6 +240,57 @@ Remove any files in the `tablelocation/data` folder which
are not known to the t
CALL catalog_name.system.remove_orphan_files(table => 'db.sample', location =>
'tablelocation/data')
```
+### `rewrite_data_files`
+
+Iceberg tracks each data file in a table. More data files leads to more
metadata stored in manifest files, and small data files causes an unnecessary
amount of metadata and less efficient queries from file open costs.
+
+Iceberg can compact data files in parallel using Spark with the
`rewriteDataFiles` action. This will combine small files into larger files to
reduce metadata overhead and runtime file open cost.
+
+#### Usage
+
+| Argument Name | Required? | Type | Description |
+|---------------|-----------|------|-------------|
+| `table` | ✔️ | string | Name of the table to update |
+| `strategy` | | string | Name of the strategy - binpack or sort.
Defaults to binpack strategy |
+| `sort_order` | | string | Comma separated sort_order_column. Where
sort_order_column is a space separated sort order info per column (ColumnName
SortDirection NullOrder). <br/> All three members are mandatory to provide for
sort_order_column. SortDirection can be ASC or DESC. NullOrder can be FIRST or
LAST |
+| `options` | ️ | map<string, string> | Options to be used for actions|
+| `where` | ️ | string | predicate as a string used for filtering the
files.|
+
+
+See the [`RewriteDataFiles` Javadoc](./javadoc/{{ versions.iceberg
}}/org/apache/iceberg/actions/RewriteDataFiles.html#field.summary),
+<br/> [`BinPackStrategy` Javadoc](./javadoc/{{ versions.iceberg
}}/org/apache/iceberg/actions/BinPackStrategy.html#field.summary)
+and <br/> [`SortStrategy` Javadoc](./javadoc/{{ versions.iceberg
}}/org/apache/iceberg/actions/SortStrategy.html#field.summary)
+for list of all the supported options for this action.
+
+#### Output
+
+| Output Name | Type | Description |
+| ------------|------|-------------|
+| `rewritten_data_files_count` | int | Number of data which were re-written by
this command |
+| `added_data_files_count` | int | Number of new data files which were
written by this command |
+
+#### Examples
+
+Rewrite the data files in table `db.sample` and align data files with table
partitioning.
+```sql
+CALL catalog_name.system.rewrite_data_files('db.sample')
+```
+
+Rewrite the data files in table `db.sample` and use sort strategy with id
column as sort order column.
+```sql
+CALL catalog_name.system.rewrite_data_files(table => 'db.sample', strategy =>
'sort', sort_order => 'id DESC LAST')
Review comment:
hmm... some consistency with SQL language would be ideal, but I don't
know if that's too much work to achieve with no clear benefit, any thoughts
around this? @RussellSpitzer
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