（GoLang）恐慌：sql：為驅動程式postgres呼叫了兩次注冊

我可能在這方面花了很多時間，所以我決定在這里嘗試。
我無法弄清楚為什么我的 Register 被呼叫了兩次？
盡我所能，它似乎在一次sql.Register()又一次地呼叫sqlx.Connect()。但是，如果我洗掉sql.Register()，則沒有驅動程式。

老實說，我對 GoLang 還是很陌生，我希望這里有任何方向。

代碼 - 不帶 sql.Register

package main

import (
    "fmt"

    "database/sql"

    "github.com/jmoiron/sqlx"
)

const (
    host     = "localhost"
    port     = 5432
    user     = "postgres"
    password = "password"
    dbname   = "sampledb"
)

/*-------------------------------------------*\
||                Functions                  ||
\*-------------------------------------------*/
// Error Checking Fn
func CheckError(err error, str string) {
    if err != nil {
        fmt.Printf("Error @ : %s\n", str)
        panic(err)
    }
}

/*-------------------------------------------*\
||                 Main()                    ||
\*-------------------------------------------*/

func main() {
    // Open DB Conn
    psqlconn := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=disable", host, port, user, password, dbname)
    // sql.Register("postgres", &pq.Driver{})
    fmt.Printf(":: Drivers ::\n%s\n", sql.Drivers())
    db, err := sqlx.Connect("postgres", psqlconn)
    CheckError(err, "Main: sqlx.connect")
    defer db.Close()
}

錯誤 - 無 sql.Register

$ go run name-generator.go 
:: Drivers ::
[]
Error @ : Main: sqlx.connect
panic: sql: unknown driver "postgres" (forgotten import?)

goroutine 1 [running]:
main.CheckError({0xc84320, 0xc000056680}, {0xc6073f, 0x5})
        C:/path/to/program.go:26  0xa7    <--- Func CheckError(): panic(err)
main.main()
        C:/path/to/program.go:40  0x125   <--- Func Main(): CheckError()
exit status 2

代碼 - 帶/ sql.Register

package main

import (
    "fmt"

    "database/sql"

    "github.com/jmoiron/sqlx"
    "github.com/lib/pq"
)

const (
    host     = "localhost"
    port     = 5432
    user     = "postgres"
    password = "password"
    dbname   = "sampledb"
)

/*-------------------------------------------*\
||                Functions                  ||
\*-------------------------------------------*/
// Error Checking Fn
func CheckError(err error, str string) {
    if err != nil {
        fmt.Printf("Error @ : %s\n", str)
        panic(err)
    }
}

/*-------------------------------------------*\
||                 Main()                    ||
\*-------------------------------------------*/

func main() {
    // Open DB Conn
    psqlconn := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=disable", host, port, user, password, dbname)
    sql.Register("postgres", &pq.Driver{})
    fmt.Printf(":: Drivers ::\n%s\n", sql.Drivers())
    db, err := sqlx.Connect("postgres", psqlconn)
    CheckError(err, "Main: sqlx.connect")
    defer db.Close()
}

錯誤 - w/ sql.Register

$ go run name-generator.go 
panic: sql: Register called twice for driver postgres

goroutine 1 [running]:
database/sql.Register({0xa98bc9, 0x8}, {0xae6680, 0xc8a950})
        C:/Program Files/Go/src/database/sql/sql.go:51  0x13d
main.main()
        C:/path/to/program.go:38  0x11b
exit status 2

其他資源

• 類似的問題，但沒有解決我的問題鏈接
• SQLX 檔案鏈接
• SQL 檔案鏈接

uj5u.com熱心網友回復：

該包github.com/lib/pq 在 init 函式中注冊它的驅動程式。

從應用程式中洗掉所有注冊驅動程式的直接呼叫：

 sql.Register("postgres", &pq.Driver{}) <-- delete this line

匯入執行函式github.com/lib/pq的副作用：init()

package main

import (
    "fmt"
    "database/sql"
    "github.com/jmoiron/sqlx"
     _ "github.com/lib/pq"  // <-- add this line
)

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