英文:
golang sqlite can't define Query variable
问题
似乎 golang 的 sqlite 包不喜欢我的 db.Query 语句，尽管它与 GitHub 上的示例 中的语句完全相同。
db, err := sql.Open("sqlite3", "./database.db")
if err != nil {
log.Fatal(err)
}
defer db.Close()
rows, err = db.Query("select id, name from job")
if err != nil {
log.Fatal(err)
}
defer rows.Close()
fmt.Println("Jobs:")
for rows.Next() {
var name string
var id int
fmt.Printf("%v %v\n", id, name)
}
这是我得到的错误：
./test.go:7: undefined: rows
./test.go:7: cannot assign to rows
./test.go:11: undefined: rows
./test.go:14: undefined: rows
编辑：我也尝试过使用重音符和单引号字符串来调用 db.Query()，但没有成功。
英文:
It seems golang's sqlite package doesn't like my db.Query statement, though it's exactly like the one found in the example on github.
db, err := sql.Open("sqlite3", "./database.db")
if err != nil {
log.Fatal(err)
}
defer db.Close()
rows, err = db.Query("select id, name from job")
if err != nil {
log.Fatal(err)
}
defer rows.Close()
fmt.Println("Jobs:")
for rows.Next() {
var name string
var id int
fmt.Printf("%v %v\n", id, name)
}
This is the error I'm getting:
./test.go:7: undefined: rows
./test.go:7: cannot assign to rows
./test.go:11: undefined: rows
./test.go:14: undefined: rows
Edit: I've tried using grave accent and single quote strings for db.Query() as well, to no avail.
答案1
得分: 4
你不能给未声明的变量赋值。
rows, err = db.Query("select id, name from job")
应该改为：
rows, err := db.Query("select id, name from job")
理论上这应该解决问题，但我还没有尝试过。
你还应该添加：
rows.Scan(&id, &name)
在printf函数之前，这样才能将行的值分配给id和name变量，否则将打印一个空字符串和0。
英文:
You cannot assign values to to undeclared variables.
rows, err = db.Query("select id, name from job")
Should be :
rows, err := db.Query("select id, name from job")
Theoretically this should solve the problem, but I haven't tried.
You should also add :
rows.Scan(&id, &name)
Before the printf function so as to actually assign the row's value to the id & name variables otherwise will print an empty string & 0.
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