我正在尝试使用选择并插入查询时获得受影响的记录数
我已尝试使用此方法进行插入查询:
recordSet.rowsAffected
,用于选择查询:
recordSet.length
但没有一个起作用。
这是我的代码:
router.route('/').post((req, res)=> {
var postData = req.body; // get post params
// res.json({"message":req.body.firstName});
connection.connect().then(function(){
var request = new sql.Request(connection);
request.input('email', sql.VarChar(45), postData.email)
.input('password', sql.VarChar(45), postData.password)
.input('category', sql.VarChar(45), postData.category)
.query('select * from Buyer where password = @password and category =
@category and email = @email')
.then((recordSet)=>{
if (recordSet.length == 0) {
request.input('buyerId', sql.VarChar(45), uid.v4())
.input('firstName', sql.VarChar(45), postData.firstName)
.input('lastName', sql.VarChar(45), postData.lastName)
.input('email', sql.VarChar(45), postData.email)
.input('password', sql.VarChar(45), postData.password)
.input('phoneNumber', sql.VarChar(45), postData.phoneNumber)
.input('category', sql.VarChar(45), postData.category)
.query('insert into Buyer(buyer_id, first_name, last_name, email,
password, phone_number, category) values(@buyerId, @firstName, @lastName,
@email, @password, @phoneNumber, @category)')
.then((recordSet)=>{
if(recordSet.rowsAffected == 1){
res.status(buyerCreatedCode).send("Account Created as
Buyer.");
}else{
res.status(buyerNotCreatedCode).send("Account not Created as
Buyer.");
}
connection.close();
}).catch((err)=>{
res.json({"error in adding buyer":err});
connection.close();
});
}else{
res.status(buyerNotCreatedCode).send("This Account already
exists.");
connection.close();
}
}).catch((err)=>{
res.json({"error in checking buyer":err});
connection.close();
});
}).catch((err)=>{
res.json({"error connection":err});
connection.close();
});
});
因此,我希望如果选择查询返回0条记录,则将买家插入数据库,如果返回记录,则不会插入买家(但无论如何都会插入)。
我的问题是如何正确获取受影响的行数,以便任务正确执行? 预先感谢。
答案 0 :(得分:1)
您应该将大部分代码功能移至SQL代码中,从中创建一个存储过程,并使用您的值进行调用。
例如,您的存储过程可能如下所示:
CREATE PROCEDURE AddBuyer
@email varchar(45), -- too small. up to 100
@password varchar(45),
@category varchar(45),
@firstname varchar(45),
@lastName varchar(45),
@phoneNumber varchar(45) -- Couldn't this be smaller?
AS
BEGIN
DECLARE @buyerId uniqueidentifier
, @error int
-- Recommended - return the message and the ID from this procedure
SELECT @buyerId = BuyerId
FROM Buyer
WHERE email = @email
AND password = @password
AND category = @category
IF @@ROWCOUNT > 0
BEGIN
-- Return the actual existing ID
SELECT @buyerId as BuyerId,
'This Account already exists.' as StatusMsg
END
ELSE
BEGIN
SET @buyerId = NewID() -- Generate UniqueIdentifier
insert into Buyer(
buyer_id,
first_name,
last_name,
email,
password,
phone_number,
category
)
values(
@buyerId,
@firstName,
@lastName,
@email,
@password,
@phoneNumber,
@category
);
SET @error = @@ERROR
IF @error > 0
BEGIN
SELECT CAST(NULL as uniqueidentifier) as BuyerId,
'Account not Created as Buyer. (Status=' + Cast(@error as varchar(10)) + ')' as StatusMsg
END
ELSE
BEGIN
SELECT @buyerId as BuyerId,
'Account Created as Buyer.' As StatusMsg
END
END
END
执行此操作时,将返回一行记录集。它由BuyerId值(错误时为NULL)和相应的消息文本组成。
变量包括返回OUTPUT变量中的值,TRY ... CATCH错误陷阱等。