mongo-go-driver详细使用示例
<div class="cnblogs_Highlighter"><pre class="brush:go;gutter:true;"> package main
import (
"context"
"log"
"go.mongodb.org/mongo-driver/bson"
"go.mongodb.org/mongo-driver/bson/primitive"
"go.mongodb.org/mongo-driver/mongo"
"go.mongodb.org/mongo-driver/mongo/options"
"go.mongodb.org/mongo-driver/mongo/readpref"
"go.mongodb.org/mongo-driver/x/bsonx"
)
type Book struct {
Id primitive.ObjectID `bson:"_id"`
Name string
Category string
Weight int
Author AuthorInfo
}
type AuthorInfo struct {
Name string
Country string
}
const (
categoryComputer = "计算机"
categorySciFi = "科幻"
countryChina = "中国"
countryAmerica = "美国"
)
var (
books = []interface{}{
&Book{
Id: primitive.NewObjectID(),
Name: "深入理解计算机操作系统",
Category: categoryComputer,
Weight: 1,
Author: AuthorInfo{
Name: "兰德尔 E.布莱恩特",
Country: countryAmerica,
},
},
&Book{
Id: primitive.NewObjectID(),
Name: "深入理解Linux内核",
Category: categoryComputer,
Weight: 1,
Author: AuthorInfo{
Name: "博韦，西斯特",
Country: countryAmerica,
},
},
&Book{
Id: primitive.NewObjectID(),
Name: "三体",
Category: categorySciFi,
Weight: 1,
Author: AuthorInfo{
Name: "刘慈欣",
Country: countryChina,
},
},
}
)
func main() {
log.SetFlags(log.Llongfile | log.LstdFlags)
opts := options.Client().ApplyURI("mongodb://localhost:27017")
// 连接数据库
client, err := mongo.Connect(context.Background(), opts)
if err != nil {
log.Fatal(err)
}
// 判断服务是不是可用
if err = client.Ping(context.Background(), readpref.Primary()); err != nil {
log.Fatal(err)
}
// 获取数据库和集合
collection := client.Database("mydb").Collection("book")
// 清空文档
err = collection.Drop(context.Background())
if err != nil {
log.Fatal(err)
}
// 设置索引
idx := mongo.IndexModel{
Keys: bsonx.Doc{{"name", bsonx.Int32(1)}},
Options: options.Index().SetUnique(true),
}
idxRet, err := collection.Indexes().CreateOne(context.Background(), idx)
if err != nil {
log.Fatal(err)
}
log.Println("collection.Indexes().CreateOne:", idxRet)
// 插入一条数据
insertOneResult, err := collection.InsertOne(context.Background(), books)
if err != nil {
log.Fatal(err)
}
log.Println("collection.InsertOne: ", insertOneResult.InsertedID)
// 插入多条数据
insertManyResult, err := collection.InsertMany(context.Background(), books)
if err != nil {
log.Fatal(err)
}
log.Println("collection.InsertMany: ", insertManyResult.InsertedIDs)
// 获取数据总数
count, err := collection.CountDocuments(context.Background(), bson.D{})
if err != nil {
log.Fatal(count)
}
log.Println("collection.CountDocuments:", count)
// 查询单条数据
var one Book
err = collection.FindOne(context.Background(), bson.M{"name": "三体"}).Decode(&one)
if err != nil {
log.Fatal(err)
}
log.Println("collection.FindOne: ", one)
// 查询多条数据(方式一)
cur, err := collection.Find(context.Background(), bson.D{})
if err != nil {
log.Fatal(err)
}
if err := cur.Err(); err != nil {
log.Fatal(err)
}
var all []*Book
err = cur.All(context.Background(), &all)
if err != nil {
log.Fatal(err)
}
cur.Close(context.Background())
log.Println("collection.Find curl.All: ", all)
for _, one := range all {
log.Println(one)
}
// 查询多条数据(方式二)
cur, err = collection.Find(context.Background(), bson.D{})
if err != nil {
log.Fatal(err)
}
if err := cur.Err(); err != nil {
log.Fatal(err)
}
for cur.Next(context.Background()) {
var b Book
if err = cur.Decode(&b); err != nil {
log.Fatal(err)
}
log.Println("collection.Find cur.Next:", b)
}
cur.Close(context.Background())
// 模糊查询
cur, err = collection.Find(context.Background(), bson.M{"name": primitive.Regex{Pattern: "深入"}})
if err != nil {
log.Fatal(err)
}
if err := cur.Err(); err != nil {
log.Fatal(err)
}
for cur.Next(context.Background()) {
var b Book
if err = cur.Decode(&b); err != nil {
log.Fatal(err)
}
log.Println("collection.Find name=primitive.Regex{深入}: ", b)
}
cur.Close(context.Background())
// 二级结构体查询
cur, err = collection.Find(context.Background(), bson.M{"author.country": countryChina})
// cur, err = collection.Find(context.Background(), bson.D{bson.E{"author.country", countryChina}})
if err != nil {
log.Fatal(err)
}
if err := cur.Err(); err != nil {
log.Fatal(err)
}
for cur.Next(context.Background()) {
var b Book
if err = cur.Decode(&b); err != nil {
log.Fatal(err)
}
log.Println("collection.Find author.country=", countryChina, ":", b)
}
cur.Close(context.Background())
// 只查询指定字段
opts := options.Find().SetProjection(bson.M{"Name": 1})
cur, err := coll.Find(context.Background(), filter, opts)
if err != nil {
return
}
all := []*Book{}
err = cur.All(context.Background(), &ret)
if err := cur.Err(); err != nil {
log.Fatal(err)
}
// 修改一条数据
b1 := books.(*Book)
b1.Weight = 2
update := bson.M{"$set": b1}
updateResult, err := collection.UpdateOne(context.Background(), bson.M{"name": b1.Name}, update)
if err != nil {
log.Fatal(err)
}
log.Println("collection.UpdateOne:", updateResult)
// 修改一条数据，如果不存在则插入
new := &Book{
Id: primitive.NewObjectID(),
Name: "球状闪电",
Category: categorySciFi,
Author: AuthorInfo{
Name: "刘慈欣",
Country: countryChina,
},
}
update = bson.M{"$set": new}
updateOpts := options.Update().SetUpsert(true)
updateResult, err = collection.UpdateOne(context.Background(), bson.M{"_id": new.Id}, update, updateOpts)
if err != nil {
log.Fatal(err)
}
log.Println("collection.UpdateOne:", updateResult)
// 删除一条数据
deleteResult, err := collection.DeleteOne(context.Background(), bson.M{"_id": new.Id})
if err != nil {
log.Fatal(err)
}
log.Println("collection.DeleteOne:", deleteResult)
}
</pre>
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<p> </p><br><br>
来源：https://www.cnblogs.com/xiaoxiongfei/p/11234227.html
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