Merge pull request #44913 from DanRoscigno/add-INFILE-docs

add example with file globbing

docs/en/sql-reference/statements/insert-into.md

@@ -91,11 +91,11 @@ INSERT INTO t FORMAT TabSeparated
 
 You can insert data separately from the query by using the command-line client or the HTTP interface. For more information, see the section “[Interfaces](../../interfaces)”.
 
-### Constraints
+## Constraints
 
 If table has [constraints](../../sql-reference/statements/create/table.md#constraints), their expressions will be checked for each row of inserted data. If any of those constraints is not satisfied — server will raise an exception containing constraint name and expression, the query will be stopped.
 
-### Inserting the Results of `SELECT`
+## Inserting the Results of `SELECT`
 
 **Syntax**
 
@@ -114,7 +114,7 @@ However, you can delete old data using `ALTER TABLE ... DROP PARTITION`.
 
 To insert a default value instead of `NULL` into a column with not nullable data type, enable [insert_null_as_default](../../operations/settings/settings.md#insert_null_as_default) setting.
 
-### Inserting Data from a File
+## Inserting Data from a File
 
 **Syntax**
 
@@ -122,14 +122,15 @@ To insert a default value instead of `NULL` into a column with not nullable data
 INSERT INTO [db.]table [(c1, c2, c3)] FROM INFILE file_name [COMPRESSION type] FORMAT format_name
 ```
 
-Use the syntax above to insert data from a file stored on a **client** side. `file_name` and `type` are string literals. Input file [format](../../interfaces/formats.md) must be set in the `FORMAT` clause. 
+Use the syntax above to insert data from a file, or files, stored on the **client** side. `file_name` and `type` are string literals. Input file [format](../../interfaces/formats.md) must be set in the `FORMAT` clause. 
 
-Compressed files are supported. Compression type is detected by the extension of the file name. Or it can be explicitly specified in a `COMPRESSION` clause. Supported types are: `'none'`, `'gzip'`, `'deflate'`, `'br'`, `'xz'`, `'zstd'`, `'lz4'`, `'bz2'`.
+Compressed files are supported. The compression type is detected by the extension of the file name. Or it can be explicitly specified in a `COMPRESSION` clause. Supported types are: `'none'`, `'gzip'`, `'deflate'`, `'br'`, `'xz'`, `'zstd'`, `'lz4'`, `'bz2'`.
 
 This functionality is available in the [command-line client](../../interfaces/cli.md) and [clickhouse-local](../../operations/utilities/clickhouse-local.md).
 
-**Example**
+**Examples**
 
+### Single file with FROM INFILE
 Execute the following queries using [command-line client](../../interfaces/cli.md):
 
 ```bash
@@ -148,7 +149,27 @@ Result:
 └────┴──────┘
 ```
 
-### Inserting into Table Function
+### Multiple files with FROM INFILE using globs
+
+This example is very similar to the previous one but inserts from multiple files using `FROM INFILE 'input_*.csv`.
+
+```bash
+echo 1,A > input_1.csv ; echo 2,B > input_2.csv
+clickhouse-client --query="CREATE TABLE infile_globs (id UInt32, text String) ENGINE=MergeTree() ORDER BY id;"
+clickhouse-client --query="INSERT INTO infile_globs FROM INFILE 'input_*.csv' FORMAT CSV;"
+clickhouse-client --query="SELECT * FROM infile_globs FORMAT PrettyCompact;"
+```
+
+:::tip
+In addition to selecting multiple files with `*`, you can use ranges (`{1,2}` or `{1..9}`) and other [glob substitutions](/docs/en/sql-reference/table-functions/file.md/#globs-in-path). These three all would work with the above example:
+```sql
+INSERT INTO infile_globs FROM INFILE 'input_*.csv' FORMAT CSV;
+INSERT INTO infile_globs FROM INFILE 'input_{1,2}.csv' FORMAT CSV;
+INSERT INTO infile_globs FROM INFILE 'input_?.csv' FORMAT CSV;
+```
+:::
+
+## Inserting into Table Function
 
 Data can be inserted into tables referenced by [table functions](../../sql-reference/table-functions/index.md).
 
@@ -176,7 +197,7 @@ Result:
 └─────┴───────────────────────┘
 ```
 
-### Performance Considerations
+## Performance Considerations
 
 `INSERT` sorts the input data by primary key and splits them into partitions by a partition key. If you insert data into several partitions at once, it can significantly reduce the performance of the `INSERT` query. To avoid this: