子查询在插入中返回多个结果答案

【问题标题】：Sub query returning multiple results within an insert子查询在插入中返回多个结果
【发布时间】：2017-09-28 13:51:07
【问题描述】：

我有下面的 SQL 尝试使用子查询插入到 Financial_history_details 表中，因为我需要该语句从表的其他部分提取数据。

只要有一行信息就可以了。我的问题是我试图插入数千行数据，其中某些信息 (batch_number, contact_number) 从不同的表中提取。

我考虑过使用这个语句中看到的子查询，但正如我已经说过的那样，它的效果并不好，因为它一次只插入一条数据。

INSERT INTO financial_history (batch_number, transaction_number, contact_number, transaction_date, 
            transaction_type, amount, payment_method, posted, address_number, currency_amount) 
VALUES ((select batch_number from event_bookings where batch_number not in (select batch_number from batches)), 1,
(select contact_number from event_bookings where batch_number not in (select batch_number from batches)),
'20-sep-2017', 'P', 0, 'CASH', '20-sep-2017', 
(select address_number from event_bookings where batch_number not in (select batch_number from batches)), 0) ;

我也尝试过使用从 CSV 导入，但这会导致许多问题，使其成为不切实际的解决方案：

BULK
INSERT batches
FROM 'C:\batches.csv'
WITH
(
FIELDTERMINATOR = ',',
ROWTERMINATOR = '\n'
)
GO

还有其他方法可以做到这一点吗？

【问题讨论】：

标签： sql sql-server-2016

【解决方案1】：

你似乎想要一个insert . . . select：

insert into financial_history (batch_number, transaction_number, contact_number, transaction_date, 
            transaction_type, amount, payment_method, posted, address_number, currency_amount) 
    select . . .
    from event_bookings
    where batch_number not in (select batch_number from batches);

不过，尚不清楚您希望列的值是什么。

【讨论】：

【解决方案2】：

您可以使用，使用单个 SELECT 并避免对同一个表重复多次访问（您也可以使用不插入的 SELECT 来检查输出）

INSERT INTO financial_history (batch_number, transaction_number, contact_number, transaction_date, 
            transaction_type, amount, payment_method, posted, address_number, currency_amount) 
SELECT batch_number, 1, contact_number, '20-sep-2017', 'P', 0, 'CASH', '20-sep-2017', address_number from event_bookings
WHERE batch_number not in (select batch_number from batches);

提示：

对日期使用 CONVERT 并且不依赖隐式转换（假设您的目标列是日期时间数据类型：例如。CONVERT(datetime,'20/09/2017', 103) 106)）

同一查询的更易读的形式：

INSERT INTO financial_history (batch_number, transaction_number, contact_number, transaction_date, 
            transaction_type, amount, payment_method, posted, address_number, currency_amount) 
SELECT batch_number
  , 1 AS TRANSACTION_NUMBER
  , contact_number
  , '20-sep-2017' AS TRANSACTION_DATE
  , 'P' AS TRANSACTION TYPE
  , 0 AS AMOUNT
  , 'CASH' AS PAYMENT_METHOD
  , '20-sep-2017' AS POSTED
  , address_number 
  FROM event_bookings
  WHERE batch_number not in (select batch_number from batches);

【讨论】：