74 lines
1.5 KiB
Go
74 lines
1.5 KiB
Go
package main
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import (
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"database/sql"
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"fmt"
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"log"
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"os"
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"github.com/go-sql-driver/mysql"
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)
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var db *sql.DB
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type Album struct {
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ID int64
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Title string
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Artist string
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Price float32
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Quantity int64
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}
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func main() {
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// Capture connection properties.
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cfg := mysql.Config{
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User: os.Getenv("DBUSER"),
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Passwd: os.Getenv("DBPASS"),
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Net: "tcp",
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Addr: "127.0.0.1:3306",
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DBName: "recordings",
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}
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// Get a database handle.
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var err error
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db, err = sql.Open("mysql", cfg.FormatDSN())
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if err != nil {
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log.Fatal(err)
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}
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pingErr := db.Ping()
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if pingErr != nil {
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log.Fatal(pingErr)
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}
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fmt.Println("Connected!")
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albums, err := albumsByArtist("John Coltrane")
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if err != nil {
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log.Fatal(err)
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}
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fmt.Printf("Albums found: %v\n", albums)
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}
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// albumsByArtist queries for albums that have the specified artist name.
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func albumsByArtist(name string) ([]Album, error) {
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// An albums slice to hold data from returned rows.
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var albums []Album
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rows, err := db.Query("SELECT * FROM album WHERE artist = ?", name)
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if err != nil {
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return nil, fmt.Errorf("albumsByArtist %q: %v", name, err)
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}
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defer rows.Close()
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// Loop through rows, using Scan to assign column data to struct fields.
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for rows.Next() {
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var alb Album
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if err := rows.Scan(&alb.ID, &alb.Title, &alb.Artist, &alb.Price, &alb.Quantity); err != nil {
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return nil, fmt.Errorf("albumsByArtist %q: %v", name, err)
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}
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albums = append(albums, alb)
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}
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if err := rows.Err(); err != nil {
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return nil, fmt.Errorf("albumsByArtist %q: %v", name, err)
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}
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return albums, nil
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}
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