spa*_*guy 2 javascript sql sequelize.js
我有两个表 (users和games) 由关联表 ( game_players) 连接,创建了多对多关系:
models.Game.belongsToMany(models.User, { through: models.GamePlayer, as: 'players' });
models.User.belongsToMany(models.Game, { through: models.GamePlayer, foreignKey: 'user_id' });
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除了外键user_idand 之外game_id,game_players还有一些额外的列用于链接特定的数据:
sequelize.define('game_player', {
isReady: {
defaultValue: false,
type: Sequelize.BOOLEAN,
field: 'is_ready'
},
isDisabled: {
defaultValue: false,
type: Sequelize.BOOLEAN,
field: 'is_disabled'
},
powerPreferences: {
type: Sequelize.TEXT,
field: 'power_preferences'
},
power: {
type: Sequelize.STRING(2),
defaultValue: '?'
}
}, {
underscored: true
});
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假设我想获取一个游戏并急切地加载活跃玩家。这是我的第一次尝试:
db.models.Game.findAll({
include: [{
model: db.models.User,
as: 'players',
where: { 'game_player.isDisabled': false }
}]
}).nodeify(cb);
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这会生成以下 SQL,它会引发错误Column players.game_player.isDisabled does not exist:
SELECT "game"."id",
"game"."name",
"game"."description",
"game"."variant",
"game"."status",
"game"."move_clock" AS "moveClock",
"game"."retreat_clock" AS "retreatClock",
"game"."adjust_clock" AS "adjustClock",
"game"."max_players" AS "maxPlayers",
"game"."created_at",
"game"."updated_at",
"game"."gm_id",
"game"."current_phase_id",
"players"."id" AS "players.id",
"players"."email" AS "players.email",
"players"."temp_email" AS "players.tempEmail",
"players"."password" AS "players.password",
"players"."password_salt" AS "players.passwordSalt",
"players"."action_count" AS "players.actionCount",
"players"."failed_action_count" AS "players.failedActionCount",
"players"."created_at" AS "players.created_at",
"players"."updated_at" AS "players.updated_at",
"players.game_player"."is_ready" AS
"players.game_player.isReady",
"players.game_player"."is_disabled" AS
"players.game_player.isDisabled",
"players.game_player"."power_preferences" AS
"players.game_player.powerPreferences",
"players.game_player"."power" AS "players.game_player.power",
"players.game_player"."created_at" AS
"players.game_player.created_at",
"players.game_player"."updated_at" AS
"players.game_player.updated_at",
"players.game_player"."game_id" AS
"players.game_player.game_id",
"players.game_player"."user_id" AS
"players.game_player.user_id"
FROM "games" AS "game"
INNER JOIN ("game_players" AS "players.game_player"
INNER JOIN "users" AS "players"
ON "players"."id" = "players.game_player"."user_id")
ON "game"."id" = "players.game_player"."game_id"
AND "players"."game_player.isdisabled" = false;
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显然,Sequelize 用不正确的引号包装了我的约束别名:'players'.'game_player.isdisabled' 应该是 'players.game_player'.isdisabled。如何修改上面的 Sequelize 代码以正确查询此列?
我明白了,但只能通过手动浏览存储库的已关闭票证并找到#4880。
使用开箱即用的连接表列的子句可以包含在$. 老实说,我不明白它的魔力,因为我发誓我没有看到任何有关它的文档。修改我上面的查询实现了我想要的:
db.models.Game.findAll({
include: [{
model: db.models.User,
as: 'players',
where: { '$players.game_player.is_disabled$': false }
}]
}).nodeify(cb);
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小智 5
查了一下,发现through.where还可以用:
db.models.Game.findAll({
include: [{
model: db.models.User,
as: 'players',
through: { where: { isDisabled: false } }
}]
})
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参考:
是否可以使用sequelize通过关联表中的属性来过滤查询?
具有多对多关系的热切加载
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