* @return the corresponding map from column keys to values
   */
  Map<C, V> row(@ParametricNullness R rowKey);

  /**
   * Returns a view of all mappings that have the given column key. For each row key / column key /
   * value mapping in the table with that column key, the returned map associates the row key with
   * the value. If no mappings in the table have the provided column key, an empty map is returned.
   *

		t.Fatalf("Failed to add column, got %v", err)
	}

	if !DB.Table("column_structs").Migrator().HasColumn(&NewColumnStruct{}, "NewName") {
		t.Fatalf("Failed to find added column")
	}

	if err := DB.Table("column_structs").Migrator().DropColumn(&NewColumnStruct{}, "NewName"); err != nil {
		t.Fatalf("Failed to add column, got %v", err)
	}

   *
   * <p>The returned map's views have iterators that don't support {@code remove()}.
   */
  @Override
  public Map<R, V> column(C columnKey) {
    return new Column(columnKey);
  }

  private class Column extends ViewCachingAbstractMap<R, V> {
    final C columnKey;

    Column(C columnKey) {
      this.columnKey = checkNotNull(columnKey);
    }

    @Override
    @CheckForNull

 *
 * <p>The allowed row and column keys must be supplied when the table is created. The table always
 * contains a mapping for every row key / column pair. The value corresponding to a given row and
 * column is null unless another value is provided.
 *
 * <p>The table's size is constant: the product of the number of supplied row keys and the number of

from sqlalchemy import Boolean, Column, ForeignKey, Integer, String
from sqlalchemy.orm import relationship

from .database import Base


class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True)
    email = Column(String, unique=True, index=True)
    hashed_password = Column(String)
    is_active = Column(Boolean, default=True)

    items = relationship("Item", back_populates="owner")

			} else if eq, ok := expr.(clause.Eq); ok {
				switch column := eq.Column.(type) {
				case string:
					assigns[column] = eq.Value
				case clause.Column:
					assigns[column.Name] = eq.Value
				}
			}
		}

		return tx.Model(dest).Updates(assigns)
	}

	return tx
}

				newName = field.DBName
			}
		}

		return m.DB.Exec(
			"ALTER TABLE ? RENAME COLUMN ? TO ?",
			m.CurrentTable(stmt), clause.Column{Name: oldName}, clause.Column{Name: newName},
		).Error
	})
}

// MigrateColumn migrate column
func (m Migrator) MigrateColumn(value interface{}, field *schema.Field, columnType gorm.ColumnType) error {
	if field.IgnoreMigration {

			builder.WriteByte('@')
			builder.WriteString(string(name))
		}
	}
}

// IN Whether a value is within a set of values
type IN struct {
	Column interface{}
	Values []interface{}
}

func (in IN) Build(builder Builder) {
	builder.WriteQuoted(in.Column)

	switch len(in.Values) {
	case 0:
		builder.WriteString(" IN (NULL)")
	case 1:
		if _, ok := in.Values[0].([]interface{}); !ok {

		ReflectValue: reflect.ValueOf(dest),
		Dest:         dest,
	}

	stmt.Schema = s

	values := ConvertToCreateValues(stmt)
	expected := clause.Values{
		// column has value + defaultValue column has value (which should have a stable order)
		Columns: []clause.Column{{Name: "name"}, {Name: "email"}, {Name: "age"}, {Name: "id"}},
		Values: [][]interface{}{
			{"alice", "email", 18, 1},
			{"bob", "email", 19, 2},
		},
	}

      table.put(row, 2, 'b');
    }
  }

  private static void populateForColumnKeySet(
      Table<Integer, String, Character> table, String[] elements) {
    for (String column : elements) {
      table.put(1, column, 'a');
      table.put(2, column, 'b');
    }
  }

  private static void populateForValues(
      Table<Integer, Character, String> table, String[] elements) {
    for (int i = 0; i < elements.length; i++) {