什么是“存储过程”，它们是如何工作的?
存储过程是由什么组成的(每个东西都必须是存储过程)?
当前回答
存储过程用于检索数据、修改数据和删除数据库表中的数据。你不需要每次在SQL数据库中插入、更新或删除数据时都写一个完整的SQL命令。
其他回答
想想这样的情况，
You have a database with data. There are a number of different applications needed to access that central database, and in the future some new applications too. If you are going to insert the inline database queries to access the central database, inside each application's code individually, then probably you have to duplicate the same query again and again inside different applications' code. In that kind of a situation, you can use stored procedures (SPs). With stored procedures, you are writing number of common queries (procedures) and store them with the central database. Now the duplication of work will never happen as before and the data access and the maintenance will be done centrally.
注意:
In the above situation, you may wonder "Why cannot we introduce a central data access server to interact with all the applications? Yes. That will be a possible alternative. But, The main advantage with SPs over that approach is, unlike your data-access-code with inline queries, SPs are pre-compiled statements, so they will execute faster. And communication costs (over networks) will be at a minimum. Opposite to that, SPs will add some more load to the database server. If that would be a concern according to the situation, a centralized data access server with inline queries will be a better choice.
存储过程用于检索数据、修改数据和删除数据库表中的数据。你不需要每次在SQL数据库中插入、更新或删除数据时都写一个完整的SQL命令。
create procedure <owner>.<procedure name><param> <datatype>
As
<body>
存储过程是将数据访问集中在一点上的SQL语句组。适用于在一个镜头中执行多个操作。
在存储过程中，语句只被写入一次，从而减少了客户端和服务器之间的网络流量。 我们也可以避免Sql注入攻击。
Incase if you are using a third party program in your application for processing payments, here database should only expose the information it needed and activity that this third party has been authorized, by this we can achieve data confidentiality by setting permissions using Stored Procedures. The updation of table should only done to the table it is targeting but it shouldn't update any other table, by which we can achieve data integrity using transaction processing and error handling. If you want to return one or more items with a data type then it is better to use an output parameter. In Stored Procedures, we use an output parameter for anything that needs to be returned. If you want to return only one item with only an integer data type then better use a return value. Actually the return value is only to inform success or failure of the Stored Procedure.
一般来说，存储过程是一个“SQL函数”。他们有:
-- a name
CREATE PROCEDURE spGetPerson
-- parameters
CREATE PROCEDURE spGetPerson(@PersonID int)
-- a body
CREATE PROCEDURE spGetPerson(@PersonID int)
AS
SELECT FirstName, LastName ....
FROM People
WHERE PersonID = @PersonID
这是一个以T-SQL为重点的示例。存储过程可以执行大多数SQL语句，返回标量值和基于表的值，并且被认为更安全，因为它们可以防止SQL注入攻击。
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