> For the complete documentation index, see [llms.txt](https://3ks.gitbook.io/ent-zh_cn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://3ks.gitbook.io/ent-zh_cn/za-xiang/sql-integration.md).

# sql.DB 集成

下面的示例将说明如何将自定义 `sql.DB`对象传递给 `ent.Client`.

## 配置 `sql.DB`

方法一：

```go
package main

import (
    "time"

    "<your_project>/ent"
    "github.com/facebookincubator/ent/dialect/sql"
)

func Open() (*ent.Client, error) {
    drv, err := sql.Open("mysql", "<mysql-dsn>")
    if err != nil {
        return nil, err
    }
    // 获取驱动的底层 sql.DB 对象。
    db := drv.DB()
    db.SetMaxIdleConns(10)
    db.SetMaxOpenConns(100)
    db.SetConnMaxLifetime(time.Hour)
    return ent.NewClient(ent.Driver(drv)), nil
}
```

方法二：

```go
package main

import (
    "database/sql"
    "time"

    "<your_project>/ent"
    entsql "github.com/facebookincubator/ent/dialect/sql"
)

func Open() (*ent.Client, error) {
    db, err := sql.Open("mysql", "<mysql-dsn>")
    if err != nil {
        return nil, err
    }
    db.SetMaxIdleConns(10)
    db.SetMaxOpenConns(100)
    db.SetConnMaxLifetime(time.Hour)
    // Create an ent.Driver from `db`.
    // 从 `db` 创建一个 ent.Driver.
    drv := entsql.OpenDB("mysql", db)
    return ent.NewClient(ent.Driver(drv)), nil
}
```

## 在 MySQL 中使用 Opencensus

> 译者注：OpenCensus 是 Google 开源的一个用来收集和追踪应用程序指标的第三方库。目前 Opencensus 已经与 OpenTracing [合并](https://www.cncf.io/blog/2019/05/21/a-brief-history-of-opentelemetry-so-far/)

```go
package main

import (
    "context"
    "database/sql"
    "database/sql/driver"

    "<project>/ent"

    "contrib.go.opencensus.io/integrations/ocsql"
    "github.com/go-sql-driver/mysql"
    entsql "github.com/facebookincubator/ent/dialect/sql"
)

type connector struct {
    dsn string
}

func (c connector) Connect(context.Context) (driver.Conn, error) {
    return c.Driver().Open(c.dsn)
}

func (connector) Driver() driver.Driver {
    return ocsql.Wrap(
        mysql.MySQLDriver{},
        ocsql.WithAllTraceOptions(),
        ocsql.WithRowsClose(false),
        ocsql.WithRowsNext(false),
        ocsql.WithDisableErrSkip(true),
    )
}

// 打开新的连接并启动统计记录器。
func Open(dsn string) *ent.Client {
    db := sql.OpenDB(connector{dsn})
    // 从 `db` 创建一个 ent.Driver.
    drv := entsql.OpenDB("mysql", db)
    return ent.NewClient(ent.Driver(drv))
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://3ks.gitbook.io/ent-zh_cn/za-xiang/sql-integration.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.