Struct Column 

pub struct Column {

    pub name: String,
    pub ty: SqlType,
    pub primary_key: bool,
    pub nullable: bool,
    pub fk_target: Option<String>,
    pub noform: bool,
    pub db_constraint: bool,
    pub noedit: bool,
    pub is_string_repr: bool,
    pub max_length: u32,
    pub choices: Vec<String>,
    pub choice_labels: Vec<String>,
    pub default: String,
    pub is_multichoice: bool,
    pub unique: bool,
    pub on_delete: FkAction,
    pub on_update: FkAction,
    pub index: bool,
    pub auto_now_add: bool,
    pub auto_now: bool,
    pub help: String,
    pub example: String,
    pub widget: Option<String>,
    pub supported_backends: Vec<String>,
    pub min: Option<i64>,
    pub max: Option<i64>,
    pub text_format: Option<String>,
    pub slug_from: Option<String>,
}

One column inside a Operation::CreateTable.

Mirrors the structure of FieldSpec but is fully owned for serialisation. Reconstructed from a FieldSpec at diff time.

Fields

name: String

ty: SqlType

primary_key: bool

nullable: bool

fk_target: Option<String>

For SqlType::ForeignKey columns: the SQL table name of the referenced model. None for all non-FK columns.

noform: bool

When true, this field is never shown on any admin form (create or edit). Propagated from FieldSpec::noform.

db_constraint: bool

For FK columns: whether to emit a physical FOREIGN KEY ... REFERENCES constraint. Propagated from FieldSpec::db_constraint. false (set via #[umbral(db_constraint = false)]) keeps the logical FK (column + fk_target) but renders no REFERENCES clause — the only valid shape for a cross-database FK. Closes gaps2 #22. Defaults to true so existing migration JSON round-trips unchanged (omitted from JSON when at its default).

noedit: bool

When true, this field appears on the edit form as read-only. Propagated from FieldSpec::noedit.

is_string_repr: bool

Display-string marker — propagated from FieldSpec::is_string_repr. The admin uses the first column with this flag as the default list_display label when no explicit one is configured.

max_length: u32

Display truncation cap — propagated from FieldSpec::max_length. 0 means no truncation.

choices: Vec<String>

Closed-set DB values for a choices column. Propagated from FieldSpec::choices. Non-empty when the model field carries #[umbral(choices)]; the migration engine emits a Postgres CHECK (col IN (...)) constraint when this slice is non-empty. Empty for every non-choices column.

choice_labels: Vec<String>

Human labels matching choices position-for-position. Carried alongside choices so the admin’s <select> widget has labels without the runtime needing to reflect on the model type.

default: String

SQL DEFAULT value — propagated from FieldSpec::default. Empty string means no default. The migration engine reads this at DDL-emit time for both CREATE TABLE and ALTER TABLE ADD COLUMN. Set via #[umbral(default = "...")] on the model field.

is_multichoice: bool

Distinguishes a multi-valued MultiChoice<E> column from a single-valued choices column. Both share ty: Text plus the same choices / choice_labels metadata; this flag is the only signal that the value is a CSV. Empty / false for every other column.

unique: bool

Carries FieldSpec::unique into the migration snapshot. The DDL builders emit a UNIQUE clause on this column at CREATE TABLE time when set. Default false keeps existing migration JSON files round-tripping unchanged (the field is omitted on serialise when default).

on_delete: FkAction

Carries FieldSpec::on_delete into the migration snapshot. FK columns only — the DDL builders emit ON DELETE <action> when this is anything other than NoAction. Default NoAction is omitted from JSON so existing migration files round-trip without churn.

on_update: FkAction

Carries FieldSpec::on_update into the migration snapshot. Same shape as on_delete; emits ON UPDATE <action>.

index: bool

Carries FieldSpec::index into the migration snapshot. The CreateTable + AddColumn render paths emit a matching CREATE INDEX idx_<table>_<col> for every column whose flag is set. Default false keeps existing migration JSON round-tripping unchanged.

auto_now_add: bool

Carries FieldSpec::auto_now_add into the migration snapshot. The dynamic write path (DynQuerySet::insert_json) auto-populates the column with Utc::now() when the body omits it. Default false so existing migration JSON round-trips unchanged.

auto_now: bool

Carries FieldSpec::auto_now into the migration snapshot. Same shape as auto_now_add but fires on update too.

help: String

Carries FieldSpec::help into the migration snapshot. Default empty string is omitted from JSON so existing migration files round-trip unchanged.

example: String

Carries FieldSpec::example into the migration snapshot. Same shape as help.

widget: Option<String>

Carries FieldSpec::widget into the migration snapshot — the form-renderer presentation hint (features.md #4). Presentation only, no DB effect, so it’s excluded from the schema diff the same way help / example are. None is omitted from JSON so existing migration files round-trip unchanged.

supported_backends: Vec<String>

Carries FieldSpec::supported_backends into the migration snapshot. When non-empty, the boot system check rejects the model on any backend not listed. Closes IMP-5 from bugs/tests/testBugs.md. Default empty (works on every backend); JSON skip-when-empty so existing migration files don’t churn.

min: Option<i64>

IMP-3: numeric lower bound. None means “no minimum”; the DDL emits a CHECK (col >= N) constraint when set.

max: Option<i64>

IMP-3: numeric upper bound. Same shape as min.

text_format: Option<String>

BUG-11/12/13: constrained-text marker. None is plain text; Some("slug" | "email" | "url") flags the column as a Slug / Email / Url wrapper. OpenAPI emits the corresponding format / pattern; the REST plugin pre-validates the body via validate_text_format.

slug_from: Option<String>

Gap 109: auto-derive source. When Some("title"), the slug is computed from the row’s title column at write time if the slug column itself is empty / missing on the body. Pure runtime behaviour — has no DDL effect, so the diff engine ignores changes to this field. #[serde(default)] keeps older snapshots round-tripping.

Trait Implementations

impl Clone for Column

fn clone(&self) -> Column

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Column

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Column

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Column

impl From<&FieldSpec> for Column

fn from(f: &FieldSpec) -> Self

Converts to this type from the input type.

impl From<&IntrospectedColumn> for Column

fn from(c: &IntrospectedColumn) -> Self

Converts to this type from the input type.

impl PartialEq for Column

fn eq(&self, other: &Column) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Column

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Column