# `Lotus.Storage.QueryVariable`
[🔗](https://github.com/typhoonworks/lotus/blob/v0.16.6/lib/lotus/storage/query_variable.ex#L1)

Represents a variable placeholder (`{{var}}`) used inside a Lotus query.

Each variable defines:
  * `:name`   — the identifier used in the SQL statement
  * `:type`   — how the value is interpreted (text, number, date)
  * `:widget` — how the value should be collected in the UI (input, select)
  * `:label`  — a human-friendly label shown in the UI
  * `:default` — fallback value if none is provided
  * `:static_options` — hardcoded list of allowed values (for selects)
    Can be either a list of strings or a list of {value, label} tuples
  * `:options_query`  — SQL to dynamically populate allowed values

Validation ensures that when a variable is configured as a `:select`
widget, it must have either `:static_options` or `:options_query`.

# `t`

```elixir
@type t() :: %Lotus.Storage.QueryVariable{
  default: String.t() | nil,
  label: String.t() | nil,
  list: boolean(),
  name: String.t(),
  options_query: String.t() | nil,
  static_options: [Lotus.Storage.QueryVariable.StaticOption.t()],
  type: :text | :number | :date,
  widget: :input | :select | nil
}
```

# `changeset`

# `get_option_source`

```elixir
@spec get_option_source(t()) :: :query | :static
```

Determines the source of options for a query variable.

Returns `:query` if the variable has a non-empty `options_query`,
otherwise returns `:static`.

## Examples

    iex> var = %Lotus.Storage.QueryVariable{options_query: "SELECT id, name FROM users"}
    iex> Lotus.Storage.QueryVariable.get_option_source(var)
    :query

    iex> var = %Lotus.Storage.QueryVariable{options_query: "   "}
    iex> Lotus.Storage.QueryVariable.get_option_source(var)
    :static

    iex> var = %Lotus.Storage.QueryVariable{static_options: ["a", "b"]}
    iex> Lotus.Storage.QueryVariable.get_option_source(var)
    :static

    iex> var = %Lotus.Storage.QueryVariable{static_options: [{"val", "Label"}]}
    iex> Lotus.Storage.QueryVariable.get_option_source(var)
    :static

---

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