toColumns method
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Implementation
@override
Map<String, Expression<Object>> toColumns(bool nullToAbsent) {
return MigrationsCompanion(
id: id == null ? const Value.absent() : Value(id!),
name: Value(name),
start: start == null ? const Value.absent() : Value(start!),
finish: finish == null ? const Value.absent() : Value(finish!),
migrationState: Value(migrationState))
.toColumns(nullToAbsent);
}