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[TOC] >[github](https://github.com/jmoiron/sqlx) ## 概述 ``` package main import ( "database/sql" "fmt" "log" _ "github.com/lib/pq" "github.com/jmoiron/sqlx" ) var schema = ` CREATE TABLE person ( first_name text, last_name text, email text ); CREATE TABLE place ( country text, city text NULL, telcode integer )` type Person struct { FirstName string `db:"first_name"` LastName string `db:"last_name"` Email string } type Place struct { Country string City sql.NullString TelCode int } func main() { // this Pings the database trying to connect // use sqlx.Open() for sql.Open() semantics db, err := sqlx.Connect("postgres", "user=foo dbname=bar sslmode=disable") if err != nil { log.Fatalln(err) } // exec the schema or fail; multi-statement Exec behavior varies between // database drivers; pq will exec them all, sqlite3 won't, ymmv db.MustExec(schema) tx := db.MustBegin() tx.MustExec("INSERT INTO person (first_name, last_name, email) VALUES ($1, $2, $3)", "Jason", "Moiron", "jmoiron@jmoiron.net") tx.MustExec("INSERT INTO person (first_name, last_name, email) VALUES ($1, $2, $3)", "John", "Doe", "johndoeDNE@gmail.net") tx.MustExec("INSERT INTO place (country, city, telcode) VALUES ($1, $2, $3)", "United States", "New York", "1") tx.MustExec("INSERT INTO place (country, telcode) VALUES ($1, $2)", "Hong Kong", "852") tx.MustExec("INSERT INTO place (country, telcode) VALUES ($1, $2)", "Singapore", "65") // Named queries can use structs, so if you have an existing struct (i.e. person := &Person{}) that you have populated, you can pass it in as &person tx.NamedExec("INSERT INTO person (first_name, last_name, email) VALUES (:first_name, :last_name, :email)", &Person{"Jane", "Citizen", "jane.citzen@example.com"}) tx.Commit() // Query the database, storing results in a []Person (wrapped in []interface{}) people := []Person{} db.Select(&people, "SELECT * FROM person ORDER BY first_name ASC") jason, john := people[0], people[1] fmt.Printf("%#v\n%#v", jason, john) // Person{FirstName:"Jason", LastName:"Moiron", Email:"jmoiron@jmoiron.net"} // Person{FirstName:"John", LastName:"Doe", Email:"johndoeDNE@gmail.net"} // You can also get a single result, a la QueryRow jason = Person{} err = db.Get(&jason, "SELECT * FROM person WHERE first_name=$1", "Jason") fmt.Printf("%#v\n", jason) // Person{FirstName:"Jason", LastName:"Moiron", Email:"jmoiron@jmoiron.net"} // if you have null fields and use SELECT *, you must use sql.Null* in your struct places := []Place{} err = db.Select(&places, "SELECT * FROM place ORDER BY telcode ASC") if err != nil { fmt.Println(err) return } usa, singsing, honkers := places[0], places[1], places[2] fmt.Printf("%#v\n%#v\n%#v\n", usa, singsing, honkers) // Place{Country:"United States", City:sql.NullString{String:"New York", Valid:true}, TelCode:1} // Place{Country:"Singapore", City:sql.NullString{String:"", Valid:false}, TelCode:65} // Place{Country:"Hong Kong", City:sql.NullString{String:"", Valid:false}, TelCode:852} // Loop through rows using only one struct place := Place{} rows, err := db.Queryx("SELECT * FROM place") for rows.Next() { err := rows.StructScan(&place) if err != nil { log.Fatalln(err) } fmt.Printf("%#v\n", place) } // Place{Country:"United States", City:sql.NullString{String:"New York", Valid:true}, TelCode:1} // Place{Country:"Hong Kong", City:sql.NullString{String:"", Valid:false}, TelCode:852} // Place{Country:"Singapore", City:sql.NullString{String:"", Valid:false}, TelCode:65} // Named queries, using `:name` as the bindvar. Automatic bindvar support // which takes into account the dbtype based on the driverName on sqlx.Open/Connect _, err = db.NamedExec(`INSERT INTO person (first_name,last_name,email) VALUES (:first,:last,:email)`, map[string]interface{}{ "first": "Bin", "last": "Smuth", "email": "bensmith@allblacks.nz", }) // Selects Mr. Smith from the database rows, err = db.NamedQuery(`SELECT * FROM person WHERE first_name=:fn`, map[string]interface{}{"fn": "Bin"}) // Named queries can also use structs. Their bind names follow the same rules // as the name -> db mapping, so struct fields are lowercased and the `db` tag // is taken into consideration. rows, err = db.NamedQuery(`SELECT * FROM person WHERE first_name=:first_name`, jason) // batch insert // batch insert with structs personStructs := []Person{ {FirstName: "Ardie", LastName: "Savea", Email: "asavea@ab.co.nz"}, {FirstName: "Sonny Bill", LastName: "Williams", Email: "sbw@ab.co.nz"}, {FirstName: "Ngani", LastName: "Laumape", Email: "nlaumape@ab.co.nz"}, } _, err = db.NamedExec(`INSERT INTO person (first_name, last_name, email) VALUES (:first_name, :last_name, :email)`, personStructs) // batch insert with maps personMaps := []map[string]interface{}{ {"first_name": "Ardie", "last_name": "Savea", "email": "asavea@ab.co.nz"}, {"first_name": "Sonny Bill", "last_name": "Williams", "email": "sbw@ab.co.nz"}, {"first_name": "Ngani", "last_name": "Laumape", "email": "nlaumape@ab.co.nz"}, } _, err = db.NamedExec(`INSERT INTO person (first_name, last_name, email) VALUES (:first_name, :last_name, :email)`, personMaps) } ```