ColumnMetadata class

Metadata for a single column in a query result.

Pure domain entity — carries only the column name and the protocol type discriminant (mirror of the Rust OdbcType enum at native/odbc_engine/src/protocol/types.rs). The numeric value is the wire protocol discriminant, not the ODBC SQL_* type code.

The richer typed view (OdbcType enum) lives in the infrastructure layer and is exposed as an extension on ColumnMetadata so the domain stays free of FFI / protocol dependencies. Consumers who need the typed view import the extension explicitly:

import 'package:odbc_fast/odbc_fast.dart';

for (final col in qr.columnsMetadata ?? const <ColumnMetadata>[]) {
  print('${col.name} -> discriminant=${col.odbcType}');
}

Discriminant table (truncated):

Discriminant	Wire type
1	varchar (UTF-8)
2	integer (i32 LE)
3	bigInt (i64 LE)
4	decimal (UTF-8)
5	date (UTF-8)
6	timestamp (UTF-8)
7	binary (raw)

See the OdbcType enum for the full mapping.

Available extensions

• ColumnMetadataTypedView

Annotations

• @immutable

Constructors

ColumnMetadata({required String name, required int odbcType})

Creates a new ColumnMetadata instance.

const

Properties

hashCode → int

The hash code for this object.

no setter, override

name → String

Column name.

final

odbcType → int

Protocol type discriminant (matches OdbcType.discriminant). Unknown discriminants degrade to varchar (1) for forward compatibility — see the typed view extension.

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

type → OdbcType

Available on ColumnMetadata, provided by the ColumnMetadataTypedView extension

no setter

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

override

Operators

operator ==(Object other) → bool

The equality operator.

override