# `Selecto.Output.Transformers.CSV`

CSV transformer for Selecto query results.

Converts query results to CSV format with configurable options:
- Headers: Include/exclude column headers
- Delimiter: Custom field separators (comma, tab, semicolon, etc.)
- Quoting: Proper escaping for special characters
- Null handling: Custom null value representation
- Streaming: Efficient processing for large datasets

## Options

- `:headers` - Include headers (default: true)
- `:delimiter` - Field separator (default: ",")
- `:quote_char` - Quote character (default: """)
- `:null_value` - Null representation (default: "")
- `:force_quotes` - Quote all fields (default: false)
- `:line_ending` - Line ending style (default: "\n")

## Examples

    iex> Selecto.Output.Transformers.CSV.transform(
    ...>   [["Alice", 25], ["Bob", 30]],
    ...>   ["name", "age"],
    ...>   ["name", "age"]
    ...> )
    {:ok, "name,age\nAlice,25\nBob,30\n"}

    iex> Selecto.Output.Transformers.CSV.transform(
    ...>   [["John, Jr.", nil]],
    ...>   ["full_name", "age"],
    ...>   ["full_name", "age"],
    ...>   delimiter: ";", null_value: "N/A"
    ...> )
    {:ok, "full_name;age\n\"John, Jr.\";N/A\n"}

# `stream_transform`

Transform query results to CSV format with streaming support.

Returns a stream that yields CSV lines (including header if configured).
Efficient for large datasets as it processes rows one at a time.

# `transform`

Transform query results to CSV format.

Returns the complete CSV as a string with optional headers and properly escaped values.

---

*Consult [api-reference.md](api-reference.md) for complete listing*