如何在MondoDB中多重更新嵌套数组? [英] How to multi update of a nested array in MondoDB?
问题描述
我在MongoDB游乐场"集合中的文档遵循以下模式":
I have documents in a MongoDB 'playground' collection following the below "schema" :
{
"_id": ObjectId("54423b40c92f9fffb486a6d4"),
"ProjectFileId": 1,
"SourceLanguageId": 2,
"TargetSegments": [
{
"LanguageId": 1,
"Segment": "Something",
"Colors": [
1,
2,
3
],
"Heights": [
1,
2,
3
],
"Widths": [
1,
2,
3
]
},
{
"LanguageId": 1,
"Segment": "Something",
"Colors": [
1,
2,
3
],
"Heights": [
1,
2,
3
],
"Widths": [
1,
2,
3
]
}
]
}
以及以下更新查询:
db.playground.update({
$and: [
{
"TargetSegments.Colors": {
$exists: true
}
},
{
"ProjectFileId": 1
},
{
"SourceLanguageId": 2
},
{
"TargetSegments": {
$elemMatch: {
"LanguageId": 1
}
}
}
]
},
{
$set: {
"TargetSegments.$.Segment": null,
"TargetSegments.$.Colors": [],
"TargetSegments.$.Widths": [],
"TargetSegments.$.Heights": []
}
},
false, true)
执行查询后,结果为:
{
"_id": ObjectId("54423b40c92f9fffb486a6d4"),
"ProjectFileId": 1,
"SourceLanguageId": 2,
"TargetSegments": [
{
"LanguageId": 1,
"Segment": null,
"Colors": [],
"Heights": [],
"Widths": []
},
{
"LanguageId": 1,
"Segment": "Something",
"Colors": [
1,
2,
3
],
"Heights": [
1,
2,
3
],
"Widths": [
1,
2,
3
]
}
]
}
如您所见,只有"TargetSegments"数组的第一个元素被更新.
As you can see, only the first element of the "TargetSegments" array is updated.
如何在一个更新查询中更新TargetSegments数组的所有元素?
How can I update all the elements of the TargetSegments array in one update query?
推荐答案
这是因为您使用的是$运算符:位置$运算符标识了数组中的一个元素(不是多元素),而无需显式更新指定元素在数组中的位置.要从读取操作中投影或返回数组元素,请参见$ projection运算符.
Its because you are using $ operator: The positional $ operator identifies an element (not multi) in an array to update without explicitly specifying the position of the element in the array. To project, or return, an array element from a read operation, see the $ projection operator.
您可以使用以下代码进行操作:
You can use below code to do it:
db.playground.find({
$and: [
{
"TargetSegments.Colors": {
$exists: true
}
},
{
"ProjectFileId": 1
},
{
"SourceLanguageId": 2
},
{
"TargetSegments": {
$elemMatch: {
"LanguageId": 1
}
}
}
]
}).forEach(function(item)
{
var targets = item.TargetSegments;
for(var index = 0; index < targets.length; index++)
{
var target = targets[index];
target.Segment = null,
target.Colors= [],
target.Widths= [],
target.Heights= []
}
db.playground.save(item);
});
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