设备所在建筑 ## 前置条件 设备已经绑定楼层 ``` FROM equipment WHERE project_id='Pj1101010015' AND floor_id is not null ``` ## 处理方式 从绑定的楼层里取建筑ID, 将建筑ID填入设备ID(建筑ID为空,则设备的建筑ID也为空)。 ## 实现方式 SQL ``` UPDATE equipment SET building_id = (SELECT build_id FROM "floor" WHERE id = equipment.floor_id) WHERE project_id='Pj1101010015' AND floor_id is not null ```