Struct ColumnDef 

pub struct ColumnDef {

    pub name: String,
    pub ty: ColumnTypeName,
    pub nullable: bool,
    pub default: Option<Expr>,
    pub auto_increment: bool,
    pub is_primary_key: bool,
    pub is_unique: bool,
    pub check: Option<Expr>,
    pub user_type_ref: Option<String>,
    pub on_update_runtime: Option<Expr>,
    pub collation: Collation,
    pub is_unsigned: bool,
    pub inline_enum_variants: Option<Vec<String>>,
    pub inline_set_variants: Option<Vec<String>>,
}

Fields

name: String

ty: ColumnTypeName

nullable: bool

default: Option<Expr>

DEFAULT <expr> literal supplied at CREATE TABLE. Engine evaluates this once (with an empty row) and caches the resulting Value on the column schema.

auto_increment: bool

MySQL-style AUTO_INCREMENT — the engine maintains a counter per such column and fills the slot when INSERT leaves it unbound (omitted from a column-list INSERT or explicitly NULL).

is_primary_key: bool

v7.9.13 — inline PRIMARY KEY column constraint. mailrs migration follow-up F1. Implies NOT NULL. Engine creates an implicit BTree index named <table>_pkey over this column at CREATE TABLE time, satisfying the parent-side index requirement for any FOREIGN KEY pointing at it.

is_unique: bool

v7.13.0 — inline UNIQUE column constraint (mailrs round-5 G2). The CREATE TABLE handler folds this into a single-column TableConstraint::Unique so the engine path stays uniform with table-level UNIQUE.

check: Option<Expr>

v7.13.0 — inline CHECK (<expr>) column constraint (mailrs round-5 G3). Stored alongside the column so the CREATE TABLE handler can fold these into table-level CHECK constraints. Multiple inline CHECKs on the same column are concatenated with AND at the table level.

user_type_ref: Option<String>

v7.17.0 Phase 1.4 — user-defined type reference. When the parser sees an unknown column-type ident (anything not in the built-in parse_column_type_name table), it sets ty = ColumnTypeName::Text and records the original name here. The engine resolves at CREATE TABLE time: if a catalog enum/domain with this name exists, the column is bound to it (label-checked on INSERT for enums; CHECK- constrained for domains); otherwise the CREATE TABLE errors with “unknown type”.

on_update_runtime: Option<Expr>

v7.17.0 Phase 2.1 — MySQL-style ON UPDATE CURRENT_TIMESTAMP column attribute. When set, an UPDATE that does NOT explicitly bind this column overrides the new value with now() (engine clock). Pre-v7.17 SPG silently accepted the syntax and never fired the override — updated_at columns from mysqldump stayed pinned at their initial DEFAULT forever, an audit Tier-S silent-failure. Generalised as a stored expression source so future shapes (ON UPDATE CURRENT_TIMESTAMP(6), ON UPDATE LOCALTIMESTAMP) reuse the same field; v7.17 only accepts CURRENT_TIMESTAMP.

collation: Collation

v7.17.0 Phase 2.5 — text collation derived from the post-fix COLLATE <name> clause (and / or the table-level COLLATE=<name> for MySQL dumps that don’t repeat it per column). Pre-2.5 SPG accepted the clause and discarded the name, leaving every column byte-compared — a Tier-S silent failure when the customer expected _ci / case_insensitive semantics. Parser normalises the raw collation name into the variants in Collation. Default Binary preserves the legacy compare path.

is_unsigned: bool

v7.17.0 Phase 4.4 — MySQL UNSIGNED modifier flag. Pre- 4.4 SPG accepted and discarded the keyword, leaving negative values silently accepted on a column the customer declared INT UNSIGNED NOT NULL. Now: the engine rejects negative INSERT / UPDATE values on UNSIGNED int columns. SPG widening to u64-shaped storage is out of v7.17 scope; the upper bound remains the signed-type max (i64::MAX for BIGINT UNSIGNED), which still strictly exceeds what every mailrs / Rails app actually uses.

inline_enum_variants: Option<Vec<String>>

v7.17.0 Phase 3.P0-36 — MySQL inline ENUM('a','b','c') value list captured at parse time. When Some, the parser recognised ENUM(...) in the type slot; the engine validates INSERT cells against this list at column_def_to_schema time and persists the variants on ColumnSchema.inline_enum_variants. None for all non-ENUM columns.

inline_set_variants: Option<Vec<String>>

v7.17.0 Phase 3.P0-37 — MySQL inline SET('a','b','c') value list. Distinct from ENUM (subset semantics rather than pick-one). None for all non-SET columns.

Trait Implementations

impl Clone for ColumnDef

fn clone(&self) -> ColumnDef

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ColumnDef

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

Formats the value using the given formatter.

impl Display for ColumnDef

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

Formats the value using the given formatter.

impl PartialEq for ColumnDef

fn eq(&self, other: &ColumnDef) -> 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 StructuralPartialEq for ColumnDef