postgres准备查询，列为变量

Question

    var SelectUser, _ = Database.Prepare("SELECT $1 FROM users WHERE id=$2 LIMIT 1;")
    var name string
    SelectUser.QueryRow("name", 1).Scan(&name)

If i do like that i got an error:

runtime error: invalid memory address or nil pointer dereference

But if column is not variable, all ok.

var SelectUser, _ = Database.Prepare("SELECT name FROM users WHERE id=$1 LIMIT 1;")
var name string
SelectUser.QueryRow(1).Scan(&name)

How can I pass columns as variables?

Answer 1

You are ignoring the error of the Database.Prepare statement. If you check the error you will realise, that it fails preparing the sql. The reason why it fails was already answered here by icza:

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