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Точечная нотация

for doc in resumes.find({"city": "Ярославль"},
                     {"fio": 1, "position": 1, "_id": 0}):
    print(doc)

mongocxx::options::find options;
options.projection(make_document(kvp("fio", 1), kvp("position", 1), kvp("_id", 0)));

for (const auto& doc : resumes.find(make_document(kvp("city", "Ярославль")), options)) {
    std::cout << bsoncxx::to_json(doc) << std::endl;
}

cursor, _ := resumes.Find(ctx,
    bson.D{{Key: "city", Value: "Ярославль"}},
    options.Find().SetProjection(bson.D{
        {Key: "fio", Value: 1}, {Key: "position", Value: 1}, {Key: "_id", Value: 0}}))

for cursor.Next(ctx) {
    var doc bson.M
    cursor.Decode(&doc)
    fmt.Println(doc)
}

resumes.find(
  { "city" => "Ярославль" },
  projection: { "fio" => 1, "position" => 1, "_id" => 0 }
).each { |doc| puts doc.inspect }

filtr = {"city": "Ярославль",
         "position": "Junior Python-разработчик"}

print("город:", resumes.count_documents({"city": "Ярославль"}))
print("город и должность:", resumes.count_documents(filtr))

for doc in resumes.find(filtr, {"fio": 1, "salary": 1, "_id": 0}):
    print(doc)

auto filtr = make_document(kvp("city", "Ярославль"),
                           kvp("position", "Junior Python-разработчик"));

std::cout << "город: " << resumes.count_documents(make_document(kvp("city", "Ярославль"))) << std::endl;
std::cout << "город и должность: " << resumes.count_documents(filtr.view()) << std::endl;

mongocxx::options::find options;
options.projection(make_document(kvp("fio", 1), kvp("salary", 1), kvp("_id", 0)));
for (const auto& doc : resumes.find(filtr.view(), options)) {
    std::cout << bsoncxx::to_json(doc) << std::endl;
}

filtr := bson.D{
    {Key: "city", Value: "Ярославль"},
    {Key: "position", Value: "Junior Python-разработчик"}}

gorod, _ := resumes.CountDocuments(ctx, bson.D{{Key: "city", Value: "Ярославль"}})
oba, _ := resumes.CountDocuments(ctx, filtr)
fmt.Println("город:", gorod)
fmt.Println("город и должность:", oba)

cursor, _ := resumes.Find(ctx, filtr,
    options.Find().SetProjection(bson.D{
        {Key: "fio", Value: 1}, {Key: "salary", Value: 1}, {Key: "_id", Value: 0}}))
for cursor.Next(ctx) {
    var doc bson.M
    cursor.Decode(&doc)
    fmt.Println(doc)
}

filtr = { "city" => "Ярославль",
          "position" => "Junior Python-разработчик" }

puts "город: " + resumes.count_documents({ "city" => "Ярославль" }).to_s
puts "город и должность: " + resumes.count_documents(filtr).to_s

resumes.find(filtr, projection: { "fio" => 1, "salary" => 1, "_id" => 0 })
       .each { |doc| puts doc.inspect }

print("salary 70000 числом: ", resumes.count_documents({"salary": 70000}))
print("salary '70000' строкой:", resumes.count_documents({"salary": "70000"}))
print("is_open True:          ", vacancies.count_documents({"is_open": True}))
print("is_open 'true':        ", vacancies.count_documents({"is_open": "true"}))
print("город с маленькой:     ", resumes.count_documents({"city": "ярославль"}))

std::cout << "salary 70000 числом:  " << resumes.count_documents(make_document(kvp("salary", 70000))) << std::endl;
std::cout << "salary '70000' строкой:" << resumes.count_documents(make_document(kvp("salary", "70000"))) << std::endl;
std::cout << "is_open true:          " << vacancies.count_documents(make_document(kvp("is_open", true))) << std::endl;
std::cout << "is_open \"true\":        " << vacancies.count_documents(make_document(kvp("is_open", "true"))) << std::endl;
std::cout << "город с маленькой:     " << resumes.count_documents(make_document(kvp("city", "ярославль"))) << std::endl;

chislom, _ := resumes.CountDocuments(ctx, bson.D{{Key: "salary", Value: 70000}})
strokoy, _ := resumes.CountDocuments(ctx, bson.D{{Key: "salary", Value: "70000"}})
istina, _ := vacancies.CountDocuments(ctx, bson.D{{Key: "is_open", Value: true}})
tekstom, _ := vacancies.CountDocuments(ctx, bson.D{{Key: "is_open", Value: "true"}})
malenkoy, _ := resumes.CountDocuments(ctx, bson.D{{Key: "city", Value: "ярославль"}})

fmt.Println("salary 70000 числом:  ", chislom)
fmt.Println("salary '70000' строкой:", strokoy)
fmt.Println("is_open true:          ", istina)
fmt.Println("is_open 'true':        ", tekstom)
fmt.Println("город с маленькой:     ", malenkoy)

puts "salary 70000 числом:   " + resumes.count_documents({ "salary" => 70000 }).to_s
puts "salary '70000' строкой:" + resumes.count_documents({ "salary" => "70000" }).to_s
puts "is_open true:          " + vacancies.count_documents({ "is_open" => true }).to_s
puts "is_open 'true':        " + vacancies.count_documents({ "is_open" => "true" }).to_s
puts "город с маленькой:     " + resumes.count_documents({ "city" => "ярославль" }).to_s

for doc in vacancies.find({"salary.from": 60000},
                       {"title": 1, "salary": 1, "_id": 0}):
    print(doc)

print("выпускники СПО:", resumes.count_documents({"education.level": "СПО"}))
print("собеседования в Москве:", interviews.count_documents({"company.city": "Москва"}))

mongocxx::options::find options;
options.projection(make_document(kvp("title", 1), kvp("salary", 1), kvp("_id", 0)));
for (const auto& doc : vacancies.find(make_document(kvp("salary.from", 60000)), options)) {
    std::cout << bsoncxx::to_json(doc) << std::endl;
}

std::cout << "выпускники СПО: " << resumes.count_documents(make_document(kvp("education.level", "СПО"))) << std::endl;
std::cout << "собеседования в Москве: " << interviews.count_documents(make_document(kvp("company.city", "Москва"))) << std::endl;

cursor, _ := vacancies.Find(ctx,
    bson.D{{Key: "salary.from", Value: 60000}},
    options.Find().SetProjection(bson.D{
        {Key: "title", Value: 1}, {Key: "salary", Value: 1}, {Key: "_id", Value: 0}}))
for cursor.Next(ctx) {
    var doc bson.M
    cursor.Decode(&doc)
    fmt.Println(doc)
}

spo, _ := resumes.CountDocuments(ctx, bson.D{{Key: "education.level", Value: "СПО"}})
msk, _ := interviews.CountDocuments(ctx, bson.D{{Key: "company.city", Value: "Москва"}})
fmt.Println("выпускники СПО:", spo)
fmt.Println("собеседования в Москве:", msk)

vacancies.find({ "salary.from" => 60000 },
               projection: { "title" => 1, "salary" => 1, "_id" => 0 })
         .each { |doc| puts doc.inspect }

puts "выпускники СПО: " + resumes.count_documents({ "education.level" => "СПО" }).to_s
puts "собеседования в Москве: " + interviews.count_documents({ "company.city" => "Москва" }).to_s

print("знают Python:", resumes.count_documents({"skills": "Python"}))

for doc in resumes.find({"experience.role": "стажёр"},
                     {"fio": 1, "_id": 0}):
    print(doc)

std::cout << "знают Python: " << resumes.count_documents(make_document(kvp("skills", "Python"))) << std::endl;

mongocxx::options::find options;
options.projection(make_document(kvp("fio", 1), kvp("_id", 0)));
for (const auto& doc : resumes.find(make_document(kvp("experience.role", "стажёр")), options)) {
    std::cout << bsoncxx::to_json(doc) << std::endl;
}

python, _ := resumes.CountDocuments(ctx, bson.D{{Key: "skills", Value: "Python"}})
fmt.Println("знают Python:", python)

cursor, _ := resumes.Find(ctx,
    bson.D{{Key: "experience.role", Value: "стажёр"}},
    options.Find().SetProjection(bson.D{{Key: "fio", Value: 1}, {Key: "_id", Value: 0}}))
for cursor.Next(ctx) {
    var doc bson.M
    cursor.Decode(&doc)
    fmt.Println(doc)
}

puts "знают Python: " + resumes.count_documents({ "skills" => "Python" }).to_s

resumes.find({ "experience.role" => "стажёр" },
             projection: { "fio" => 1, "_id" => 0 })
       .each { |doc| puts doc.inspect }

print("всего резюме:", resumes.count_documents({}))
print("всего собеседований:", interviews.count_documents({}))

std::cout << "всего резюме: " << resumes.count_documents(make_document()) << std::endl;
std::cout << "всего собеседований: " << interviews.count_documents(make_document()) << std::endl;

vsego, _ := resumes.CountDocuments(ctx, bson.D{})
sobes, _ := interviews.CountDocuments(ctx, bson.D{})
fmt.Println("всего резюме:", vsego)
fmt.Println("всего собеседований:", sobes)

puts "всего резюме: " + resumes.count_documents({}).to_s
puts "всего собеседований: " + interviews.count_documents({}).to_s