在 Go 中连接到 Oracle DB

Question

我正在尝试从 Windows（64 位 Go，32 位客户端）连接到 Oracle DB

我已经提出了这个问题，但我对 Go 完全陌生，所以我对他建议的配置一无所知。

我安装了多个客户端，例如：

1. `code.google.com\p\odbc`
2. `github.com\mattn\go-oci8`

我试图创建oci8.pc文件，但似乎是错误的。

prefix=/devel/target/1.0
exec_prefix=${prefix}
libdir=C:/oracle/instantclient_12_1/sdk/lib/msvc
includedir=C:/oracle/instantclient_12_1/sdk/include
oralib=C:/oracle/instantclient_12_1/sdk/lib/msvc
orainclude=C:/oracle/instantclient_12_1/sdk/include
gcclib=C:/TDM-GCC-64/lib
gccinclude=C:/TDM-GCC-64/include
glib_genmarshal=glib-genmarshal
gobject_query=gobject-query
glib_mkenums=glib-mkenums
Name: oci8
Version: 12.1
Description: oci8 library
Libs: -L${oralib} -L${gcclib} -loci
Libs.private:
Cflags: -I${orainclude} -I${gccinclude}

当我运行以下代码时，出现错误：

// TestDB
package main

import (
"github.com/odbc"
)

func main() {
conn, _ := odbc.Connect("DSN=lnxcepd1db01.XXXXXX.com:51521*CBPDEV;UID=XXXXX;PWD=XXXXX")
defer conn.Close()

stmt, _ := conn.Prepare("select * from XXXXX where XXXX = ?")
defer stmt.Close()

stmt.Execute("100044")
rows, _ := stmt.FetchAll()
for i, row := range rows {
println(i, row)
}

}

错误：

panic: runtime error: invalid memory address or nil pointer dereference
    panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x8 pc=0x43c3a6]

goroutine 1 [running]:
github.com/odbc.(*Connection).Close(0x0, 0x45)
    C:/Go/UDL/src/github.com/odbc/odbc.go:263 +0x26
github.com/odbc.(*Connection).newStmt(0x0, 0x36, 0xc0820120e0)
    C:/Go/UDL/src/github.com/odbc/odbc.go:152 +0x50
github.com/odbc.(*Connection).Prepare(0x0, 0x51cf70, 0x36, 0x0, 0x0, 0x0, 0xc082005e90, 0x9d6eb0)
    C:/Go/UDL/src/github.com/odbc/odbc.go:162 +0x51
main.main()
    C:/Go/My Codes/new/TestDB.go:12 +0xc4

goroutine 17 [syscall, locked to thread]:
runtime.goexit()
    c:/go/src/runtime/asm_amd64.s:2232 +0x1

我错过了什么吗？ 如果有人能指出我正确的方向，我将非常感激。

提前致谢。

编辑：

浏览更多后，我将代码更改如下：

// TestDB
package main

import (
_ "code.google.com/p/odbc"
    "database/sql"
    "fmt"
)

func main() {
fmt.Println(sql.Drivers())

db, err := sql.Open("odbc","DSN=lnxcepd1db01.xxxx.com:51521*CBPDEV;UID=XXXX;PWD=XXXX")
if err != nil {
        panic(err)
}

rows, err := db.Query("select TABLE_NAME from tabs")

var TABLE_NAME string 

defer rows.Close()
    for rows.Next() {
        fmt.Println(rows.Columns())
         rows.Scan(&TABLE_NAME)
     fmt.Println(TABLE_NAME)
    }
    err = rows.Err()

    if err != nil {
        panic(err)
    }

    defer db.Close()

}

输出+错误堆栈：

[odbc]
panic: runtime error: invalid memory address or nil pointer dereference
    panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x20 pc=0x453408]

goroutine 1 [running]:
database/sql.(*Rows).Close(0x0, 0x0, 0x0)
    c:/go/src/database/sql/sql.go:1659 +0x38
database/sql.(*Rows).Next(0x0, 0xc082002400)
    c:/go/src/database/sql/sql.go:1586 +0x2c
main.main()
    C:/Go/My Codes/new/TestDB.go:23 +0x263

goroutine 2 [runnable]:
runtime.forcegchelper()
    c:/go/src/runtime/proc.go:90
runtime.goexit()
    c:/go/src/runtime/asm_amd64.s:2232 +0x1

goroutine 3 [runnable]:
runtime.bgsweep()
    c:/go/src/runtime/mgc0.go:82
runtime.goexit()
    c:/go/src/runtime/asm_amd64.s:2232 +0x1

goroutine 4 [runnable]:
runtime.runfinq()
    c:/go/src/runtime/malloc.go:712
runtime.goexit()
    c:/go/src/runtime/asm_amd64.s:2232 +0x1

goroutine 5 [runnable]:
database/sql.(*DB).connectionOpener(0xc08205a000)
    c:/go/src/database/sql/sql.go:588
created by database/sql.Open
    c:/go/src/database/sql/sql.go:452 +0x323

如您所见，当我打印可用的驱动程序时，我得到odbc ，我不确定我错过了什么。

我正在使用这个 odbc 驱动程序。

https://code.google.com/p/odbc/wiki/GettingStartedOnWindows

我注意到一件事：

当我使用

db, err := sql.Open("odbc", "DSN=lnxcepd1db01.XXXXX.com:51521;USERID=XXXX;PASSWORD=XXXX;DATABASE=CBPDEV")

我得到错误，

%v SQLDriverConnect: {IM002} [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified

当我尝试时，

db, err := sql.Open("odbc", "DSN=lnxcepd1db01.XXXXXX.com:51521*CBPDEV;UID=XXXX;PWD=XXXXX")

我得到错误：

SQLDriverConnect: {IM010} [Microsoft][ODBC Driver Manager] Data source name too long

还有这个：

db, err := sql.Open("odbc","DSN=lnxcepd1db01.XXXXX.com:51521*cbpdev;UID=XXX;PWD=XXXX")

错误：

SQLDriverConnect: {IM010} [Microsoft][ODBC Driver Manager] Data source name too long

我完全迷失了，因为我无法将其与驱动程序问题、代码问题或连接字符串中的某些参数联系起来。

我有以下问题：

我的连接字符串有什么问题？ 有没有人有从 API 构建开始的工作设置或说明（我很抱歉，但我尝试了一些但没有运气）？ 哪个 API 更好或更易于使用？

Answer 1

这是一个执行完整 conn/prep/query/fetch 操作的函数：

func getDatePrepQuery(driver string, connString string) error {
    db, err := sql.Open(driver, connString)
    if err != nil {
        log.Printf("sql.Open(%s, %s)\n\t%s\n",
            driver, connString, err.Error())
        return err
    }
    defer db.Close()

    query := "select SYSDATE from dual"
    stmt, err := db.Prepare(query)
    if err != nil {
        log.Printf("db.Prepare(%s) failed.\n\t%s\n", query, err.Error())
        return err
    }
    defer stmt.Close()

    rows, err := stmt.Query()
    if err != nil {
        log.Printf("stmt.Query() failed.\n\t%s\n", err.Error())
        return err
    }
    defer rows.Close()

    var columns []string
    columns, err = rows.Columns()
    if err != nil {
        log.Printf("rows.Columns() failed.\n\t%s\n", err.Error())
    }
    for i, c := range columns {
        fmt.Printf("%3d %s\n", i, c)
    }

    for rows.Next() {
        var sysdate time.Time
        err = rows.Scan(&sysdate)
        if err != nil {
            log.Printf("rows.Scan(...) failed.\n\t%s\n", err.Error())
            return err
        }
        fmt.Println("SYSDATE:", sysdate)
    }
    err = rows.Err()
    if err != nil {
        log.Printf("rows iteration failed.\n\t%s\n", err.Error())
        return err
    }
    return nil
}

使用 Scan 是一个棘手的部分，因为 Oracle 程序员可能不习惯它。 这个函数适用于我尝试过的所有 odbc、mgodbc、oci8、adodb 和 goracle 包。

Answer 2

您收到的错误表示您正在尝试访问未初始化变量（nil 值）上的“方法”。 在使用返回的值之前，您应该检查没有错误。

package main

import (
    "github.com/odbc"
    "log"
)

func main() {
    conn, err := odbc.Connect("DSN=lnxcepd1db01.XXXXXX.com:51521*CBPDEV;UID=XXXXX;PWD=XXXXX")
    if err != nil {
        log.Println(log)
        return
    }
    defer conn.Close()

    stmt, err := conn.Prepare("select * from XXXXX where XXXX = ?")
    if err != nil {
        log.Println(log)
        return
    }
    defer stmt.Close()

    stmt.Execute("100044")
    rows, _ := stmt.FetchAll()
    for i, row := range rows {
        println(i, row)
    }

}

Answer 3

本博客： https : //blogs.oracle.com/developers/developing-microservices-in-java%2c-javascript%2c-python%2c-net%2c-and-go-with-the-oracle-converged-database

以及它指向的研讨会和存储库，特别是https://github.com/oracle/microservices-datadriven/tree/main/grabdish/inventory-go ，可能会有所帮助。

这是片段...

source...

import (
   "context"
   "database/sql"
   "github.com/godror/godror"
)

user := os.Getenv("DB_USER")
dbpassword := os.Getenv("DB_PASSWORD") 
connectString := os.Getenv("DB_CONNECT_STRING") //for example "examplepdb_tp"
connectionString := user + "/" + dbpassword + "@" + connectString
connection, err := sql.Open("godror", connectionString)
Dockerfile...

FROM alpine:latest
ENV LD_LIBRARY_PATH=/lib
RUN wget https://download.oracle.com/otn_software/linux/instantclient/193000/instantclient-basic-linux.x64-19.3.0.0.0dbru.zip && \
    unzip instantclient-basic-linux.x64-19.3.0.0.0dbru.zip && \
    cp -r instantclient_19_3/* /lib && \
    rm -rf instantclient-basic-linux.x64-19.3.0.0.0dbru.zip && \
    apk add libaio && \
    apk add libaio libnsl libc6-compat
RUN cd /lib
RUN ln -s /lib64/* /lib
RUN ln -s libnsl.so.2 /usr/lib/libnsl.so.1
RUN ln -s /lib/libc.so.6 /usr/lib/libresolv.so.2
COPY /go/bin/inventory-go /usr/lib/inventory-go
ENTRYPOINT ["/usr/lib/inventory-go"]
Dockerfile (including build)...

FROM golang:alpine AS builder
RUN apk update && apk add --no-cache git build-base
WORKDIR /src
COPY . .
RUN go get -d -v
RUN go build -o /go/bin/inventory-go

FROM alpine:latest
ENV LD_LIBRARY_PATH=/lib
RUN wget https://download.oracle.com/otn_software/linux/instantclient/193000/instantclient-basic-linux.x64-19.3.0.0.0dbru.zip && \
    unzip instantclient-basic-linux.x64-19.3.0.0.0dbru.zip && \
    cp -r instantclient_19_3/* /lib && \
    rm -rf instantclient-basic-linux.x64-19.3.0.0.0dbru.zip && \
    apk add libaio && \
    apk add libaio libnsl libc6-compat
RUN cd /lib
RUN ln -s /lib64/* /lib
RUN ln -s libnsl.so.2 /usr/lib/libnsl.so.1
RUN ln -s /lib/libc.so.6 /usr/lib/libresolv.so.2
COPY --from=builder /go/bin/inventory-go /usr/lib/inventory-go
ENTRYPOINT ["/usr/lib/inventory-go"]