How to project all nested documents from an array of objects? - regex

Question

I have a document like this:
{
"_id": "5ffc130e9fb31b26162e0bad",
"results": [
{
"customer": {
"display_name": "Manno Dispensary - first",
"ext_acct_id": "267"
}
},
{
"customer": {
"display_name": "Manno Dispensary - second",
"ext_acct_id": "262"
}
},
{
"customer": {
"display_name": "Kako Dispensary - first",
"ext_acct_id": "261"
}
},
{
"customer": {
"display_name": "Kako Dispensary - second",
"ext_acct_id": "263"
}
}
]
}
I want to write a MongoDB query which does a regex search on "customer.display_name" and returns all those documents in results that satisfies this criteria.
I have written this query till now, and it returns me the desired output, but the problem is, it is only retuning one document inside results, Am I missing anything in this?
my desired output:
{
"_id": "5ffc130e9fb31b26162e0bad",
"results": [
{
"customer": {
"display_name": "Manno Dispensary - first",
"ext_acct_id": "267"
}
},
{
"customer": {
"display_name": "Manno Dispensary - second",
"ext_acct_id": "262"
}
}
]
}
What I am actually getting:
{
"_id": "5ffc130e9fb31b26162e0bad",
"results": [
{
"customer": {
"display_name": "Manno Dispensary - first",
"ext_acct_id": "267"
}
}
]
}
this is the query which I have written to fetch all customers which contain "Manno" in their customer name.
My collection name is Order(mongoose), search="Manno"
Order.find({
results: {
$elemMatch : {
"customer.display_name": {$regex: search}
}
}
},{
results: {
$elemMatch : {
"customer.display_name": {$regex: search}
}
}
});

Answer 1

The $elemMatch and $ will return only single matching document/object form array, try $filter and $regexMatch,
$filter to iterate loop of results array
$regexMatch to check regular expression condition, it will return true or false
Order.find({
results: {
$elemMatch: {
"customer.display_name": { $regex: "Manno" }
}
}
},
{
results: {
$filter: {
input: "$results",
cond: {
$regexMatch: {
input: "$$this.customer.display_name",
regex: "Manno"
}
}
}
}
})
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