pub struct ColumnDef {Show 25 fields
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 unique_nulls_not_distinct: bool,
pub constraint_deferrable: bool,
pub constraint_initially_deferred: bool,
pub check: Option<Expr>,
pub user_type_ref: Option<String>,
pub on_update_runtime: Option<Expr>,
pub collation: Collation,
pub collation_explicit: bool,
pub collation_name: Option<String>,
pub is_unsigned: bool,
pub inline_enum_variants: Option<Vec<String>>,
pub inline_set_variants: Option<Vec<String>>,
pub generated_stored_expr: Option<Box<Expr>>,
pub identity_always: bool,
pub mysql_int_width: Option<MysqlIntWidth>,
pub mysql_fsp: Option<u8>,
pub mysql_declared_timestamp: bool,
pub mysql_float_md: Option<(u8, u8)>,
}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: boolMySQL-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: boolv7.9.13 — 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: boolv7.13.0 — 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.
unique_nulls_not_distinct: boolv7.38 (read01 P4.19) — UNIQUE NULLS NOT DISTINCT (PG 15+) on the
inline column constraint: treat NULL keys as equal so only one NULL
is allowed. Ignored unless is_unique. Folded into the table-level
TableConstraint::Unique { nulls_not_distinct }.
constraint_deferrable: boolv7.39 (round 711) — DEFERRABLE [INITIALLY DEFERRED] written on the
inline PK/UNIQUE column constraint. Consumed since round 621; carried
since this round so the fold into the table-level constraint keeps it.
constraint_initially_deferred: bool§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: Collationv7.17.0 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.
collation_explicit: boolv7.39 (round 370, M4 P4a) — whether collation came from an
explicit COLLATE <name> clause rather than the default. Under the
MySQL dialect a text column with NO explicit clause takes the
folding default collation, while an explicit COLLATE utf8mb4_bin
stays byte-wise — and both resolve to Collation::Binary, so this
flag is the only thing that tells them apart.
collation_name: Option<String>v7.39 (round 676) — the collation name AS WRITTEN, because
collation above cannot carry it: Collation is a two-variant
MySQL enum and from_collation_name folds C, POSIX, en_US and
default all into Binary. pg_attribute.attcollation needs to
tell them apart.
is_unsigned: boolv7.17.0 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.
generated_stored_expr: Option<Box<Expr>>v7.37.7(sentori Epic 3 P1)— GENERATED ALWAYS AS (<expr>) STORED computed-column source. When Some, the engine
stores the Display-form of the parsed expression on
ColumnSchema.generated_stored_expr at CREATE TABLE time
and re-evaluates the expression against every INSERT /
UPDATE candidate row, overwriting whatever the caller
supplied for this column. Boxed to keep ColumnDef from
blowing past the large_enum_variant clippy ceiling
(Expr widens with vector literals).
identity_always: boolv7.38 (read01) — GENERATED ALWAYS AS IDENTITY (as opposed to
GENERATED BY DEFAULT AS IDENTITY). Both flavours set
auto_increment; this additionally marks the ALWAYS one, whose
explicit INSERT value PG rejects (“cannot insert a non-DEFAULT
value into column …”) unless the INSERT carries OVERRIDING SYSTEM VALUE. Only meaningful when the column is also an identity column.
mysql_int_width: Option<MysqlIntWidth>v7.39 (round 386, type-fidelity epic P1) — the declared MySQL narrow
integer width (TINYINT / MEDIUMINT), captured before the type
collapses to SmallInt / Int. The engine copies it to
ColumnSchema.mysql_int_width at CREATE TABLE time so the write
path can enforce the real range. None for every other column and
under the PG dialect.
mysql_fsp: Option<u8>v7.39 (round 424, type-fidelity epic) — the declared MySQL
fractional-seconds precision of a temporal column (DATETIME(3) is
Some(3); a bare DATETIME / TIME / TIMESTAMP is Some(0),
MySQL’s default). The engine copies it to ColumnSchema.mysql_fsp at
CREATE TABLE time so the write path can truncate and the render path
can pad. None under the PG dialect, where temporal columns keep full
microseconds.
mysql_declared_timestamp: boolv7.39.2 — the column was written TIMESTAMP rather than
DATETIME in a MySQL session. The engine copies it to
ColumnSchema.mysql_declared_timestamp at CREATE TABLE.
mysql_float_md: Option<(u8, u8)>v7.39.3 — a MySQL FLOAT(m,d) / DOUBLE(m,d) pair, copied to
ColumnSchema.mysql_float_md at CREATE TABLE.