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alexedwards/gist:dc3145c8e2e6d2fd6cd9

Last active October 15, 2025 17:51
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Revisions

  1. alexedwards revised this gist Jun 13, 2015. 1 changed file with 1 addition and 0 deletions.
    1 change: 1 addition & 0 deletions gistfile2.go
    View file
    Original file line number Diff line number Diff line change
    @@ -19,6 +19,7 @@ func main() {
    if err != nil {
    log.Fatal(err)
    }
    defer db.Close()

    rows, err := db.Query("SELECT * FROM books")
    if err != nil {
  2. alexedwards revised this gist Jun 13, 2015. 1 changed file with 7 additions and 1 deletion.
    8 changes: 7 additions & 1 deletion gistfile2.go
    View file
    Original file line number Diff line number Diff line change
    @@ -48,4 +48,10 @@ func main() {
    }
    fmt.Printf("%s, %s, %s, %s\n", bk.Isbn, bk.Title.String, bk.Author.String, price)
    }
    }
    }

    // Should output:

    // 978-1503261969, Emma, Jayne Austen, £9.44
    // 978-1514274873, Journal of a Soldier, , £5.49
    // 978-1503379640, The Prince, Niccolò Machiavelli, PRICE NOT SET
  3. alexedwards created this gist Jun 13, 2015.
    11 changes: 11 additions & 0 deletions gistfile1.sql
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,11 @@
    CREATE TABLE books (
    isbn char(14) NOT NULL,
    title varchar(255),
    author varchar(255),
    price decimal(5,2)
    );

    INSERT INTO books (isbn, title, author, price) VALUES
    ('978-1503261969', 'Emma', 'Jayne Austen', 9.44),
    ('978-1514274873', 'Journal of a Soldier', NULL, 5.49),
    ('978-1503379640', 'The Prince', 'Niccolò Machiavelli', NULL);
    51 changes: 51 additions & 0 deletions gistfile2.go
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,51 @@
    package main

    import (
    _ "github.com/lib/pq"
    "database/sql"
    "fmt"
    "log"
    )

    type Book struct {
    Isbn string
    Title sql.NullString
    Author sql.NullString
    Price sql.NullFloat64
    }

    func main() {
    db, err := sql.Open("postgres", "postgres://user:pass@localhost/bookstore")
    if err != nil {
    log.Fatal(err)
    }

    rows, err := db.Query("SELECT * FROM books")
    if err != nil {
    log.Fatal(err)
    }
    defer rows.Close()

    bks := make([]*Book, 0)
    for rows.Next() {
    bk := new(Book)
    err := rows.Scan(&bk.Isbn, &bk.Title, &bk.Author, &bk.Price)
    if err != nil {
    log.Fatal(err)
    }
    bks = append(bks, bk)
    }
    if err = rows.Err(); err != nil {
    log.Fatal(err)
    }

    for _, bk := range bks {
    var price string
    if bk.Price.Valid {
    price = fmt.Sprintf("£%.2f", bk.Price.Float64)
    } else {
    price = "PRICE NOT SET"
    }
    fmt.Printf("%s, %s, %s, %s\n", bk.Isbn, bk.Title.String, bk.Author.String, price)
    }
    }