Method RenameColumn

backend/store/model/database.go:1125–1168

RenameColumn renames a column in the table. Returns an error if the old column doesn't exist or new column already exists.

(oldName string, newName string)

// RenameColumn renames a column in the table.
// Returns an error if the old column doesn't exist or new column already exists.
func (t *TableMetadata) RenameColumn(oldName string, newName string) error {
	if oldName == newName {
		return nil
	}

	// Check if old column exists
	oldColumn := t.GetColumn(oldName)
	if oldColumn == nil {
		return errors.Errorf("column %q does not exist in table %q", oldName, t.proto.Name)
	}

	// Check if new column already exists
	if t.GetColumn(newName) != nil {
		return errors.Errorf("column %q already exists in table %q", newName, t.proto.Name)
	}

	// Remove from internal map using old name
	oldColumnID := normalizeNameByCaseSensitivity(oldName, t.isDetailCaseSensitive)
	delete(t.internalColumn, oldColumnID)

	// Update the column name in the proto
	oldColumn.proto.Name = newName

	// Add back to internal map using new name
	newColumnID := normalizeNameByCaseSensitivity(newName, t.isDetailCaseSensitive)
	t.internalColumn[newColumnID] = oldColumn

	// Update column references in indexes
	for _, index := range t.internalIndexes {
		for i, expr := range index.proto.Expressions {
			if t.isDetailCaseSensitive {
				if expr == oldName {
					index.proto.Expressions[i] = newName
				}
			} else {
				if strings.EqualFold(expr, oldName) {
					index.proto.Expressions[i] = newName
				}
			}
		}
	}

	return nil
}

func (t *ExternalTableMetadata) GetProto() *storepb.ExternalTableMetadata {
	return t.proto