Find listings with host verifications and size in MongoDB
Find all listings with listing_url, name, address, host_verificationand size of host_verification array in the listingsAndReviews collection that have a host with at least 3 verifications.
Structure of 'listingsAndReviews' collection:
{
_id: '10059872',
listing_url: 'https://www.airbnb.com/rooms/10059872',
name: 'Soho Cozy, Spacious and Convenient',
summary: 'Clean, fully furnish, Spacious 1 bedroom flat just off the escalator in Mid Levels. 2 minutes From Soho Bar and Restaurants. Located in a quiet alley 1 minute from Sun Yat Sen',
space: '',
description: 'Clean, fully furnish, Spacious 1 bedroom flat just off the escalator in Mid Levels. 2 minutes From Soho Bar and Restaurants. Located in a quiet alley 1 minute from Sun Yat Sen',
neighborhood_overview: '',
notes: '',
transit: '',
access: '',
interaction: '',
house_rules: '',
property_type: 'Apartment',
room_type: 'Entire home/apt',
bed_type: 'Real Bed',
minimum_nights: '4',
maximum_nights: '20',
cancellation_policy: 'flexible',
last_scraped: ISODate("2019-03-11T04:00:00.000Z"),
calendar_last_scraped: ISODate("2019-03-11T04:00:00.000Z"),
first_review: ISODate("2015-12-19T05:00:00.000Z"),
last_review: ISODate("2018-03-27T04:00:00.000Z"),
accommodates: 3,
bedrooms: 1,
beds: 2,
number_of_reviews: 3,
bathrooms: Decimal128("1.0"),
amenities: [
'Air conditioning',
'Kitchen',
'Smoking allowed',
'Doorman',
'Elevator',
'Heating',
'Family/kid friendly',
'Essentials',
'24-hour check-in',
'translation missing: en.hosting_amenity_50'
],
price: Decimal128("699.00"),
weekly_price: Decimal128("5000.00"),
extra_people: Decimal128("0.00"),
guests_included: Decimal128("1"),
images: {
thumbnail_url: '',
medium_url: '',
picture_url: 'https://a0.muscache.com/im/pictures/4533a1dc-6fd8-4167-938d-391c6eebbc19.jpg?aki_policy=large',
xl_picture_url: ''
},
host: {
host_id: '51624384',
host_url: 'https://www.airbnb.com/users/show/51624384',
host_name: 'Giovanni',
host_location: 'Hong Kong, Hong Kong',
host_about: '',
host_thumbnail_url: 'https://a0.muscache.com/im/pictures/264b82a7-756f-4da8-b607-dc9759e2a10f.jpg?aki_policy=profile_small',
host_picture_url: 'https://a0.muscache.com/im/pictures/264b82a7-756f-4da8-b607-dc9759e2a10f.jpg?aki_policy=profile_x_medium',
host_neighbourhood: 'Soho',
host_is_superhost: false,
host_has_profile_pic: true,
host_identity_verified: false,
host_listings_count: 1,
host_total_listings_count: 1,
host_verifications: [ 'email', 'phone', 'reviews', 'jumio', 'government_id' ]
},
address: {
street: 'Hong Kong, Hong Kong Island, Hong Kong',
suburb: 'Central & Western District',
government_area: 'Central & Western',
market: 'Hong Kong',
country: 'Hong Kong',
country_code: 'HK',
location: {
type: 'Point',
coordinates: [ 114.15027, 22.28158 ],
is_location_exact: true
}
},
availability: {
availability_30: 0,
availability_60: 0,
availability_90: 0,
availability_365: 0
},
review_scores: {
review_scores_accuracy: 10,
review_scores_cleanliness: 10,
review_scores_checkin: 10,
review_scores_communication: 10,
review_scores_location: 10,
review_scores_value: 8,
review_scores_rating: 100
},
reviews: [
{
_id: '56904633',
date: ISODate("2015-12-19T05:00:00.000Z"),
listing_id: '10059872',
reviewer_id: '5302612',
reviewer_name: 'Octavio',
comments: 'The host canceled this reservation 11 days before arrival. This is an automated posting.'
},
{
_id: '223175530',
date: ISODate("2018-01-01T05:00:00.000Z"),
listing_id: '10059872',
reviewer_id: '48436743',
reviewer_name: 'Ross',
comments: 'Giovanni was very helpful and responsive to my questions. This is a great apartment that is very convenient for exploring Hong Kong.'
},
{
_id: '247251577',
date: ISODate("2018-03-27T04:00:00.000Z"),
listing_id: '10059872',
reviewer_id: '111288273',
reviewer_name: 'Christian',
comments: 'The host canceled this reservation 8 days before arrival. This is an automated posting.'
}
]
},
.......
Query:
db.listingsAndReviews.aggregate([
{
$match: {
"host.host_verifications": { $exists: true },
$expr: { $gte: [{ $size: "$host.host_verifications" }, 3] }
}
},
{
$project: {
"listing_url": 1,
"name": 1,
"address": 1,
"host.host_verifications": 1,
"host_verifications_count": { $size: "$host.host_verifications" }
}
}
])
Output:
{
_id: '10059872',
listing_url: 'https://www.airbnb.com/rooms/10059872',
name: 'Soho Cozy, Spacious and Convenient',
host: {
host_verifications: [ 'email', 'phone', 'reviews', 'jumio', 'government_id' ]
},
address: {
street: 'Hong Kong, Hong Kong Island, Hong Kong',
suburb: 'Central & Western District',
government_area: 'Central & Western',
market: 'Hong Kong',
country: 'Hong Kong',
country_code: 'HK',
location: {
type: 'Point',
coordinates: [ 114.15027, 22.28158 ],
is_location_exact: true
}
},
host_verifications_count: 5
},
{
_id: '10059244',
listing_url: 'https://www.airbnb.com/rooms/10059244',
name: 'Ligne verte - à 15 min de métro du centre ville.',
host: {
host_verifications: [ 'email', 'phone', 'reviews', 'jumio', 'government_id' ]
},
address: {
street: 'Montréal, Québec, Canada',
suburb: 'Hochelaga-Maisonneuve',
government_area: 'Mercier-Hochelaga-Maisonneuve',
market: 'Montreal',
country: 'Canada',
country_code: 'CA',
location: {
type: 'Point',
coordinates: [ -73.54949, 45.54548 ],
is_location_exact: false
}
},
host_verifications_count: 5
},
.....
Explanation:
The said query in MongoDB that retrieves all the documents with the listing_url, name, address, host_verifications, and size of host_verification fields from the listingsAndReviews collection that have at least 3 or more host verifications.
The $exists operator checks whether the "host_verifications" field exists in the "host" subdocument.
The $expr operator evaluates the $gte expression to compare the size of the "host_verifications" array in the "host" subdocument with 3, and ensures that the host has at least 3 verifications.
The $project stage includes the listing_url, name, address, host_verifications, and size of host_verification fields .
The $size operator calculates the size of the "host_verifications" array and it adds a new field named "host_verifications_count" to the output documents.
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