MongoDB可以按照数组元素的顺序或指定顺序精确过滤,而不考虑顺序。来源:
https://savecode.net/code/javascript/mongodb+filter+by+exactly+array+elements+without+regard+to+order+or+specified+order。
db.inventory.insertMany([
{ item: "journal", qty: 25, tags: ["blank", "red"], dim_cm: [ 14, 21 ] },
{ item: "notebook", qty: 50, tags: ["red", "blank"], dim_cm: [ 14, 21 ] },
{ item: "paper", qty: 100, tags: ["red", "blank", "plain"], dim_cm: [ 14, 21 ] },
{ item: "planner", qty: 75, tags: ["blank", "red"], dim_cm: [ 22.85, 30 ] },
{ item: "postcard", qty: 45, tags: ["blue"], dim_cm: [ 10, 15.25 ] }
]);
db.inventory.find({ "tags": { "$size" : 2, "$all": [ "red", "blank" ] } });
[
{
_id: ObjectId("6179333c97a0f2eeb98a6e02"),
item: 'journal',
qty: 25,
tags: [ 'blank', 'red' ],
dim_cm: [ 14, 21 ]
},
{
_id: ObjectId("6179333c97a0f2eeb98a6e03"),
item: 'notebook',
qty: 50,
tags: [ 'red', 'blank' ],
dim_cm: [ 14, 21 ]
},
{
_id: ObjectId("6179333c97a0f2eeb98a6e05"),
item: 'planner',
qty: 75,
tags: [ 'blank', 'red' ],
dim_cm: [ 22.85, 30 ]
}
]
db.inventory.find( { tags: ["blank", "red"] } )
[
{
_id: ObjectId("6179333c97a0f2eeb98a6e02"),
item: 'journal',
qty: 25,
tags: [ 'blank', 'red' ],
dim_cm: [ 14, 21 ]
},
{
_id: ObjectId("6179333c97a0f2eeb98a6e05"),
item: 'planner',
qty: 75,
tags: [ 'blank', 'red' ],
dim_cm: [ 22.85, 30 ]
}
]
db.inventory.find( { tags: { $all: ["red", "blank"] } } )
[
{
_id: ObjectId("6179333c97a0f2eeb98a6e02"),
item: 'journal',
qty: 25,
tags: [ 'blank', 'red' ],
dim_cm: [ 14, 21 ]
},
{
_id: ObjectId("6179333c97a0f2eeb98a6e03"),
item: 'notebook',
qty: 50,
tags: [ 'red', 'blank' ],
dim_cm: [ 14, 21 ]
},
{
_id: ObjectId("6179333c97a0f2eeb98a6e05"),
item: 'planner',
qty: 75,
tags: [ 'blank', 'red' ],
dim_cm: [ 22.85, 30 ]
}
]
$eq
一样),但不检查顺序的解决方案吗? - kasoban