Question

我有一个我想用来过滤查询的uuid字符串列表。如果我循环遍历列表中的元素，我可以使查询起作用：

for i, fileUID := range fileUIDs {
    db.Exec("DELETE FROM files WHERE uid = $1::uuid", fileUID)
}

但我想使用列表让它工作：

db.Exec("DELETE FROM files WHERE uid IN $1::uuid[]", fileUIDs)

这可能吗？我似乎无法让它发挥作用。

我在How to execute an IN lookup in SQL using Golang?中尝试了解决方案但在使用pq: syntax error at or near ","时使用普通?或pq: syntax error at or near "::"时出现?:uuid错误。我使用了以下内容：

fileUIDArgs := make([]interface{}, len(fileUIDs))
for i, fileUID := range fileUIDs {
    fileUIDArgs[i] = interface{}(fileUID)
}
//also tried using "?::uuid"
myPsql := "DELETE FROM files WHERE uid IN (" + "?" + strings.Repeat(",?", len(uidStrings)-1) + ")"
db.Exec(myPsql, fileUIDArgs...)

Answer 1

使用fmt。确保您的uuids不包含任何SQL-injection。

ary := []string{
    "1442edc8-9e1f-4213-8622-5610cdd66790",
    "0506ca17-d254-40b3-9ef0-bca6d15ad49d",
    "e46f3708-6da5-4b82-9c92-f89394dffe5d",
    "fb8bf848-73a2-4253-9fa3-e9d5e16ef94a",
    "84691fa5-3391-4c02-9b16-82389331b7ac",
    "adba3c9d-b4ab-4e62-a650-414970645be7",
}
query := fmt.Sprintf(`DELETE FROM files WHERE uid IN ('%s'::uuid);`,
             strings.Join(ary, "'::uuid,'"))
db.Exec(query) // etc

play.golang.org

摆脱潜在的SQL注入：

ary := []string{ /* list of uuids */ }
query := `DELETE FROM files WHERE uid IN (`
aryInterfaces := make([]interface{}, len(ary))
for i, v := range ary {
    query += "$" + strconv.FormatInt(int64(i+1), 10)
    if i < len(ary)-1 {
        query += ","
    }
    aryInterfaces[i] = v
}
query += ")"
db.Exec(query, aryInterface...)

play.golang.org

<强>奖金 Postgresql使用$1, $2, $3等而不是?, ?, ?。这是一个小helper function和here是它的概念证明。

Answer 2

这是一个老问题，但为了将被引导到这里的人，如果您使用的是 postgres db，您可以使用这种更简单的方法：

DELETE FROM files WHERE uid=ANY($1);

$1 是一个 uuid 数组。所以你的查询变成：

toBeDeleted:= []uuid.UUID{....}
_, err = tx.Exec("UDELETE FROM files WHERE uid=ANY($1);",toBeDeleted)

//or

_, err = tx.Exec("UDELETE FROM files WHERE uid=ANY($1);",pq.Array(toBeDeleted))

两者都适合你。

Go Select In使用uuid字符串列表

2 个答案: