# tab_separated_with_names

## Description

Escaped tab-separated fields with a first row of column names.

Input and output. Select it with `FORMAT tab_separated_with_names`. Names ignore ASCII case; use the snake_case name shown here.

The first escaped tab-separated row contains names, followed by ordinary data rows. Input can match names to destination columns using the format's header settings.

There is no type row. Use the names-and-types variant when type metadata must be checked as part of the import.

```text
SELECT expressions FORMAT tab_separated_with_names;
INSERT INTO table [(columns)] [SETTINGS ...] FORMAT tab_separated_with_names
<data>
```

## Example usage

```sql
SELECT CAST(7 AS Int64) AS id, 'Ada' AS name FORMAT tab_separated_with_names;
```

```text
id	name
7	Ada
```

## Format settings

Use a statement `SETTINGS` clause; these options are not persisted by `SET`.

| Setting                          | Type     | Default | Meaning                                                                                                             |
| -------------------------------- | -------- | ------- | ------------------------------------------------------------------------------------------------------------------- |
| `ignore_unknown_fields`          | `Bool`   | `0`     | Skip input keys and header names that match no target column instead of failing.                                    |
| `snappy_mode`                    | `String` | `basic` | Read Snappy client files as basic (Hadoop blocks) or framed (standard streaming format).                            |
| `tab_separated_crlf`             | `Bool`   | `0`     | End each written row with a carriage return and a line feed instead of a line feed.                                 |
| `tab_separated_empty_as_default` | `Bool`   | `0`     | Give an empty field the column's DEFAULT instead of reading it as empty text.                                       |
| `tab_separated_enum_by_number`   | `Bool`   | `0`     | Read a whole number in an Enum column as the label's number instead of its name.                                    |
| `tab_separated_match_names`      | `Bool`   | `1`     | Match input names to target columns ignoring ASCII case; when off, skip the names header and read in target order.  |
| `tab_separated_null_text`        | `String` | `\N`    | The field text that stands for NULL when reading and writing; it cannot contain tabs or line breaks.                |
| `tab_separated_skip_lines`       | `UInt64` | `0`     | Ignore this many lines at the start of the input, before any header row.                                            |
| `tab_separated_uneven_rows`      | `Bool`   | `0`     | Accept rows with too few or too many fields: missing fields take the column's DEFAULT and extra fields are dropped. |