使用
findAll()与
include()和
sequelize.fn()为
COUNT：
Location.findAll({ attributes: { include: [[Sequelize.fn("COUNT", Sequelize.col("sensors.id")), "sensorCount"]] }, include: [{ model: Sensor, attributes: [] }]});或者，您可能还需要添加一个
group：
Location.findAll({ attributes: { include: [[Sequelize.fn("COUNT", Sequelize.col("sensors.id")), "sensorCount"]] }, include: [{ model: Sensor, attributes: [] }], group: ['Location.id']})
