whereSamePrimaryKey method

void whereSamePrimaryKey(Insertable<D> d)

Applies a where statement so that the row with the same primary key as d will be matched.

Implementation

void whereSamePrimaryKey(Insertable<D> d) {
  final source = _sourceTable;
  assert(
      source.$primaryKey.isNotEmpty,
      'When using Query.whereSamePrimaryKey, which is also called from '
      'DeleteStatement.delete and UpdateStatement.replace, the affected table'
      'must have a primary key. You can either specify a primary implicitly '
      'by making an integer() column autoIncrement(), or by explictly '
      'overriding the primaryKey getter in your table class. You\'ll also '
      'have to re-run the code generation step.\n'
      'Alternatively, if you\'re using DeleteStatement.delete or '
      'UpdateStatement.replace, consider using DeleteStatement.go or '
      'UpdateStatement.write respectively. In that case, you need to use a '
      'custom where statement.');

  final primaryKeyColumns = Map.fromEntries(source.$primaryKey.map((column) {
    return MapEntry(column.$name, column);
  }));

  final updatedFields = d.toColumns(false);
  // Construct a map of [GeneratedColumn] to [Expression] where each column is
  // a primary key and the associated value was extracted from d.
  final primaryKeyValues = Map.fromEntries(updatedFields.entries
          .where((entry) => primaryKeyColumns.containsKey(entry.key)))
      .map((columnName, value) {
    return MapEntry(primaryKeyColumns[columnName]!, value);
  });

  Expression<bool?>? predicate;
  for (final entry in primaryKeyValues.entries) {
    final comparison =
        _Comparison(entry.key, _ComparisonOperator.equal, entry.value);

    if (predicate == null) {
      predicate = comparison;
    } else {
      predicate = predicate & comparison;
    }
  }

  whereExpr = Where(predicate!);
}