如何在 golang 中运行返回已删除实体 ID 的删除查询

Question

询问 ：DELETE FROM *tableName* RETURNING *id*如何在我的 golang 代码中运行这个查询？我试过resp, err := pgConnPool.Exec(context.Background(), deleteQuery)但它给出了 pgConn.CommandTag（可用于获取 rowsCount 但不是实际行）

Answer 1

查询没问题（只需确保它以 结尾RETURNING *id*）。

假设您只删除一个实体，您可以QueryRow按照@mkopriva 的建议使用

package yourpackage

import (

  "context"

  "github.com/google/uuid"

  "github.com/jackc/pgx/v4"

)

func YourMethod() {

  // ...

  var recordID uuid.UUID

  err := pgConnPool.QueryRow(context.Background(), deleteQuery).Scan(&recordID)

  if err != nil {

    // handle error.

  }

  // recordID now contains the id of the deleted record.

}

或者包裹在处理程序中

package yourpackage

import (

  "context"

  "github.com/google/uuid"

  "github.com/jackc/pgx/v4"

)

func DeleteRecord(/*your args*/) (uuid.UUID, error) {

  var recordID uuid.UUID

  // build your deleteQuery object.

  err := pgConnPool.QueryRow(context.Background(), deleteQuery).Scan(&recordID)

  return recordID, err

}

如果你想增加一次删除多条记录的可能性

package yourpackage

import (

  "context"

  "github.com/google/uuid"

  "github.com/jackc/pgx/v4"

)

func DeleteRecords(/*your args*/) ([]uuid.UUID, error) {

  var recordIDs []uuid.UUID

  // build your deleteQuery object.

  rows, err := pgConnPool.Query(context.Background(), deleteQuery)

  if err != nil {

    return nil, err

  }

  defer rows.Close()

  for rows.Next() {

    var recordID uuid.UUID

    if err := rows.Scan(&recordID); err != nil {

      return nil, err

    }

    recordIDs = append(recordIDs, recordID)

  }

  return recordIDs, rows.Err() // Ensure no reading error occurred  

}