Background Information:
In Python, I might write something like this if I want to apply the same logic to different values in a list.
database_list = ["db_1", "db_2", "db_3"]
for x in range(0,len(database_list),1):
print("the database name is " + database_list[x])
What I am trying to do:
What I am trying to do in SSMS, is pull a list of DB objects for each database. I created a stored procedure to pull exactly what I want, but I have to run it against each database, so 10 databases mean running it 10 times.
My goal is to do this with a T-SQL query instead of Python.
I tried doing something like this:
exec sp_MSforeachdb 'USE ?; EXEC [dbo].[my_stored_procedure]';
The problem with this is, [dbo].[my_stored_procedure] has to exist in every database I want to do this in.
How can I create the stored procedure in 1 database, but execute it for all databases or a list of databases that I choose?
I know what you are trying to do and if it's what I think (you seem reluctant to actually say!) you can do the following:
In the master database, create your procedure. Normally you wouldn't do this, but in this case you must prefix it sp_
use master
go
create procedure sp_testproc as
select top 10 * from sys.tables
go
Now if you run this, it will return tables from the master database.
If you switch context to another database and exec master.dbo.sp_testproc, it will still return tables from the master database.
In master, run
sys.sp_MS_marksystemobject sp_testproc
Now switch context to a different database and exec master.dbo.sp_testproc
It will return tables from the database you are using.
Try creating your sproc in master and naming it with an sp_ prefix:
USE master
GO
CREATE PROCEDURE sp_sproc_name
AS
BEGIN
...
END
GO
-- You *may* need to mark it as a system object
EXEC sys.sp_MS_marksystemobject sp_sprocname
See: https://nickstips.wordpress.com/2010/10/18/sql-making-a-stored-procedure-available-to-all-databases/
It should then be available in all dbs
Create the stored procedure in the Master database with the sp_ prefix, and use dynamic SQL in the stored procedure so it resolves object names relative to the current database, rather than the database which contains the stored procedure.
EG
use master
go
CREATE OR ALTER PROCEDURE [dbo].[sp_getobjects]
AS
exec ('
select *
from [sys].[objects]
where is_ms_shipped = 0
order by type, name
')
go
use AdventureWorks2017
exec sp_getobjects
#LunchBox - it's your single stored procedure (that you create in one database) that is actually going to need to contain the "exec sp_MSforeach ...." command, and instead of the command to be executed being "EXEC ", it will need to be the actual SQL that you were going to put into the stored proc.
Eg. (inside your single stored procedure)
EXEC sp_MSforeachdb 'USE ?; SELECT * FROM <table>; UPDATE <another table> SET ...';
Think of the stored procedure (that you put into one database) as being no different than your Python code file - if you had actually wanted to achieve the same thing in Python, you would have either needed to create the stored proc in each database, or build the SQL statement string in Python and execute it against each database.
I understand what you thought you might be able to achieve with SQL, but stored procedures really don't work the way you were expecting. Even when you're in the context of a different database, but you run EXEC <different_db>.stored_proc, that stored proc ends up running in the context of the database in which it exists (not your context database).
Now, the only one issue you may come up against is that the standard sp_MSforeachdb stored proc has a limit of 2000 characters for the command that can be executed (although, it does have multiple "command" parameters, this may not be practical if you were planning on running a very large code block, perhaps with variables that carry all the way through). If this is something that might impact what you're intending to do, you could do a search online for "sp_MSforeachdb alternatives" - there seem to be a handful that people have created where the command parameter can contain a larger string.
When I created my stored procedure somehow I managed to place it within the stored procedures folder, however not inside the system stored procedures folder (the system SP folder exists within the stored procedures folder). How do I move it one level down into the system stored procedures folder?
EDIT: After reading the answers below I'm thinking that the problem is how I'm telling my C# program to access the stored procedure. I have this line of code that is throwing an exception, telling me that it cannot find it:
SqlCommand cmd = new SqlCommand("<database_name>.dbo.<stored_procedure_name>.sql", conn);
If anyone can offer any help on how to call the stored procedure properly it would be appreciated. Thx!
You don't, or at the least shouldn't.
This is for system stored procedures, which are built into the RDBMS and used for system functions, like renaming objects or checking users on the server.
Don't think of these as folders like in a file system - they are just organizing your objects based on existing meta-data (Stored procedure or View? System object or User object?)
You can conceivably mark it as a system object, but that's just a terrible idea.
Why do you want to obfuscate your procedure? If you are creating it it's obviously a user procedure and not a system one.
I'm really not sure why you would need to do this, but you can:
exec sp_ms_marksystemobject myprocname
It's undocumented - so I you won't have any support if you try and use it, and it might be removed from a future version of SQL Server.
+1 for #JNK's comment above.
Also, ensure that you've created the stored procedure under the schema you think you did. If you execute a statement like this:
create procedure foobar as ...
the stored procedure foobar gets created under your default schema, which is likely not dbo. You should always create and reference database objects with at least a 2-level, schema-qualified name:
create procedure dbo.foobar ...
create procedure some_schema.foobar ...
lest you shoot yourself in the foot. You should schema-qualify references as well. References like
select * from some_table
exec some_stored_procedure
rather than
select * from dbo.some_table
exec dbo.some_stored_procedure
are resolved by first probing for an object of the desired name and type under your default schema. If found, that is the object used to resolve the reference. If no such object is found, then a probe is made under the schema dbo.
Further, you should not generally give a stored procedure a name that begins with sp_: that further complicates (and slows down) resolution, throwing probes of the master database into the mix.
Someone here mentioned that We should avoid naming stored procedures in MS SQL server like sp_XXX
Because that taking addition time to SQL server while check does exist system sotred procedure named like that. Because all system stored procs are starting with sp_.
Now I wondering is that a case with Functions in MSSQL, Does naming functions like fn_ take additional time to SQL while looking for system functions ?
No, I don't think so.
Found the following thread:
http://bytes.com/topic/sql-server/answers/78872-udf-starting-fn_
No. To call a system-supplied [User Defined Function], you
need to use ::, so that is what SQL
Server looks for. All system-supplied
UDFs are table functions, as scalar
system functions are not UDFs at all.
Hope this helps
For functions it does not matter, however it is recommended to NOT use a prefix of sp_ for stored procedures as it defines a system stored procedure and may cause an extra lookup in the MASTER database.
As sp_ prefix is reserved for system
stored procedure and any stored
procedure which has sp_ prefix will
cause an extra lookup in MASTER
database. There is another point to
note that if a stored procedure uses
same name, in user database as system
stored procedure in master database,
the stored procedure in user database
will never get executed as SQL Server
will always look first in master
database and will execute that one
rather one in user database.
http://furrukhbaig.wordpress.com/2007/08/22/stored-procedures-factssheet/
http://msdn.microsoft.com/en-us/library/dd172115.aspx
I hava a stored procedure named PROC_fetchTableInfo (simple select from sys.tables) in a database named
Cust
I would like use this procedure in a another database named
Dept
I tried to execute this sp in this database using command
EXECUTE Cust.dbo.PROC_fetchTableInfo
but as a result I get tables from the database Cust. How to get this procedure to work in database Dept?
A stored procedure is tighly bound to the objects in its code. If Cust.dbo.PROC_fetchTable references a table T, that is stricly the table T in schema dbo in database Cust. You can invoke the procedure from any other place, it will always refer to this table.
If you need to run the same procedure in another table on another database then the best solution, by far, is to have a new procedure: Dept.dbo.PROC_fetxTableInfo. This is better than the alternative of using Dynamic-SQL. While this seems counteruintuitive from a DRY and code reuse perspective, T-SQL is a data access language is not a programming language, leave your C/C# mind set at the door when you enter the database. Just have another procedure in the Dept database.
Your procedure, Cust.dbo.PROC_fetchTableInfo looks at data in the Cust database. Sounds like you need a copy of it in the Dept database.
Alternately (and quite unsatisfactory to me) you can add a parameter that controls which database to query by building the query in the sproc dynamically.
Perhaps you could create it in some "Common" database and call it like EXEC Common..PROC_fetchTableInfo #databaseName='Dept'
This is possible (if you are trying to write some utility function that you can use across all databases). You can create it in the master database, give it a sp_ prefix and mark it as a system object.
use master
go
CREATE PROCEDURE dbo.sp_sys_tables_select
AS
SELECT * FROM sys.tables
GO
EXEC sys.sp_MS_marksystemobject 'dbo.sp_sys_tables_select'
GO
EXEC tempdb.dbo.sp_sys_tables_select
EXEC msdb.dbo.sp_sys_tables_select
What is a "stored procedure" and how do they work?
What is the make-up of a stored procedure (things each must have to be a stored procedure)?
Stored procedures are a batch of SQL statements that can be executed in a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CREATE PROCEDURE <owner>.<procedure name>
<Param> <datatype>
AS
<Body>
So for example:
CREATE PROCEDURE Users_GetUserInfo
#login nvarchar(30)=null
AS
SELECT * from [Users]
WHERE ISNULL(#login,login)=login
A benefit of stored procedures is that you can centralize data access logic into a single place that is then easy for DBA's to optimize. Stored procedures also have a security benefit in that you can grant execute rights to a stored procedure but the user will not need to have read/write permissions on the underlying tables. This is a good first step against SQL injection.
Stored procedures do come with downsides, basically the maintenance associated with your basic CRUD operation. Let's say for each table you have an Insert, Update, Delete and at least one select based on the primary key, that means each table will have 4 procedures. Now take a decent size database of 400 tables, and you have 1600 procedures! And that's assuming you don't have duplicates which you probably will.
This is where using an ORM or some other method to auto generate your basic CRUD operations has a ton of merit.
A stored procedure is a set of precompiled SQL statements that are used to perform a special task.
Example: If I have an Employee table
Employee ID Name Age Mobile
---------------------------------------
001 Sidheswar 25 9938885469
002 Pritish 32 9178542436
First I am retrieving the Employee table:
Create Procedure Employee details
As
Begin
Select * from Employee
End
To run the procedure on SQL Server:
Execute Employee details
--- (Employee details is a user defined name, give a name as you want)
Then second, I am inserting the value into the Employee Table
Create Procedure employee_insert
(#EmployeeID int, #Name Varchar(30), #Age int, #Mobile int)
As
Begin
Insert Into Employee
Values (#EmployeeID, #Name, #Age, #Mobile)
End
To run the parametrized procedure on SQL Server:
Execute employee_insert 003,’xyz’,27,1234567890
--(Parameter size must be same as declared column size)
Example: #Name Varchar(30)
In the Employee table the Name column's size must be varchar(30).
A stored procedure is a group of SQL statements that has been created and stored in the database. A stored procedure will accept input parameters so that a single procedure can be used over the network by several clients using different input data. A stored procedures will reduce network traffic and increase the performance. If we modify a stored procedure all the clients will get the updated stored procedure.
Sample of creating a stored procedure
CREATE PROCEDURE test_display
AS
SELECT FirstName, LastName
FROM tb_test;
EXEC test_display;
Advantages of using stored procedures
A stored procedure allows modular programming.
You can create the procedure once, store it in the database, and call it any number of times in your program.
A stored procedure allows faster execution.
If the operation requires a large amount of SQL code that is performed repetitively, stored procedures can be faster. They are parsed and optimized when they are first executed, and a compiled version of the stored procedure remains in a memory cache for later use. This means the stored procedure does not need to be reparsed and reoptimized with each use, resulting in much faster execution times.
A stored procedure can reduce network traffic.
An operation requiring hundreds of lines of Transact-SQL code can be performed through a single statement that executes the code in a procedure, rather than by sending hundreds of lines of code over the network.
Stored procedures provide better security to your data
Users can be granted permission to execute a stored procedure even if they do not have permission to execute the procedure's statements directly.
In SQL Server we have different types of stored procedures:
System stored procedures
User-defined stored procedures
Extended stored Procedures
System-stored procedures are stored in the master database and these start with a sp_ prefix. These procedures can be used to perform a variety of tasks to support SQL Server functions for external application calls in the system tables
Example: sp_helptext [StoredProcedure_Name]
User-defined stored procedures are usually stored in a user database and are typically designed to complete the tasks in the user database. While coding these procedures don’t use the sp_ prefix because if we use the sp_ prefix first, it will check the master database, and then it comes to user defined database.
Extended stored procedures are the procedures that call functions from DLL files. Nowadays, extended stored procedures are deprecated for the reason it would be better to avoid using extended stored procedures.
Generally, a stored procedure is a "SQL Function." They have:
-- 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
This is a T-SQL focused example. Stored procedures can execute most SQL statements, return scalar and table-based values, and are considered to be more secure because they prevent SQL injection attacks.
Think of a situation like this,
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.
NOTE:
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.
A stored procedure is mainly used to perform certain tasks on a database. For example
Get database result sets from some business logic on data.
Execute multiple database operations in a single call.
Used to migrate data from one table to another table.
Can be called for other programming languages, like Java.
A stored procedure is nothing but a group of SQL statements compiled into a single execution plan.
Create once time and call it n number of times
It reduces the network traffic
Example: creating a stored procedure
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE PROCEDURE GetEmployee
#EmployeeID int = 0
AS
BEGIN
SET NOCOUNT ON;
SELECT FirstName, LastName, BirthDate, City, Country
FROM Employees
WHERE EmployeeID = #EmployeeID
END
GO
Alter or modify a stored procedure:
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE GetEmployee
#EmployeeID int = 0
AS
BEGIN
SET NOCOUNT ON;
SELECT FirstName, LastName, BirthDate, City, Country
FROM Employees
WHERE EmployeeID = #EmployeeID
END
GO
Drop or delete a stored procedure:
DROP PROCEDURE GetEmployee
A stored procedure is used to retrieve data, modify data, and delete data in database table. You don't need to write a whole SQL command each time you want to insert, update or delete data in an SQL database.
A stored procedure is a precompiled set of one or more SQL statements which perform some specific task.
A stored procedure should be executed stand alone using EXEC
A stored procedure can return multiple parameters
A stored procedure can be used to implement transact
"What is a stored procedure" is already answered in other posts here. What I will post is one less known way of using stored procedure. It is grouping stored procedures or numbering stored procedures.
Syntax Reference
; number as per this
An optional integer that is used to group procedures of the same name. These grouped procedures can be dropped together by using one DROP PROCEDURE statement
Example
CREATE Procedure FirstTest
(
#InputA INT
)
AS
BEGIN
SELECT 'A' + CONVERT(VARCHAR(10),#InputA)
END
GO
CREATE Procedure FirstTest;2
(
#InputA INT,
#InputB INT
)
AS
BEGIN
SELECT 'A' + CONVERT(VARCHAR(10),#InputA)+ CONVERT(VARCHAR(10),#InputB)
END
GO
Use
exec FirstTest 10
exec FirstTest;2 20,30
Result
Another Attempt
CREATE Procedure SecondTest;2
(
#InputA INT,
#InputB INT
)
AS
BEGIN
SELECT 'A' + CONVERT(VARCHAR(10),#InputA)+ CONVERT(VARCHAR(10),#InputB)
END
GO
Result
Msg 2730, Level 11, State 1, Procedure SecondTest, Line 1 [Batch Start Line 3]
Cannot create procedure 'SecondTest' with a group number of 2 because a procedure with the same name and a group number of 1 does not currently exist in the database.
Must execute CREATE PROCEDURE 'SecondTest';1 first.
References:
CREATE PROCEDURE with the syntax for number
Numbered Stored Procedures in SQL Server - techie-friendly.blogspot.com
Grouping Stored Procedures - sqlmag
CAUTION
After you group the procedures, you can't drop them individually.
This feature may be removed in a future version of Microsoft SQL Server.
for simple,
Stored Procedure are Stored Programs, A program/function stored into database.
Each stored program contains a body that consists of an SQL statement. This statement may be a compound statement made up of several statements separated by semicolon (;) characters.
CREATE PROCEDURE dorepeat(p1 INT)
BEGIN
SET #x = 0;
REPEAT SET #x = #x + 1; UNTIL #x > p1 END REPEAT;
END;
A stored procedure is a named collection of SQL statements and procedural logic i.e, compiled, verified and stored in the server database. A stored procedure is typically treated like other database objects and controlled through server security mechanism.
In a DBMS, a stored procedure is a set of SQL statements with an assigned name that's stored in the database in compiled form so that it can be shared by a number of programs.
The use of a stored procedure can be helpful in
Providing a controlled access to data (end users can only enter or change data, but can't write procedures)
Ensuring data integrity (data would be entered in a consistent manner) and
Improves productivity (the statements of a stored procedure need to be written only once)
Stored procedures in SQL Server can accept input parameters and return multiple values of output parameters; in SQL Server, stored procedures program statements to perform operations in the database and return a status value to a calling procedure or batch.
The benefits of using stored procedures in SQL Server
They allow modular programming.
They allow faster execution.
They can reduce network traffic.
They can be used as a security mechanism.
Here is an example of a stored procedure that takes a parameter, executes a query and return a result. Specifically, the stored procedure accepts the BusinessEntityID as a parameter and uses this to match the primary key of the HumanResources.Employee table to return the requested employee.
> create procedure HumanResources.uspFindEmployee `*<<<---Store procedure name`*
#businessEntityID `<<<----parameter`
as
begin
SET NOCOUNT ON;
Select businessEntityId, <<<----select statement to return one employee row
NationalIdNumber,
LoginID,
JobTitle,
HireData,
From HumanResources.Employee
where businessEntityId =#businessEntityId <<<---parameter used as criteria
end
I learned this from essential.com...it is very useful.
Stored Procedure will help you to make code in server.You can pass parameters and find output.
create procedure_name (para1 int,para2 decimal)
as
select * from TableName
In Stored Procedures statements are written only once and reduces network traffic between clients and servers.
We can also avoid Sql Injection Attacks.
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.
Preface: In 1992 the SQL92 standard was created and was popularised by the Firebase DB. This standard introduced the 'Stored Procedure'.
**
Passthrough Query: A string (normally concatenated programatically) that evaluates to a syntactically correct SQL statement, normally generated at the server tier (in languages such as PHP, Python, PERL etc). These statements are then passed onto the database.
**
**
Trigger: a piece of code designed to fire in response to a database event (typically a DML event) often used for enforcing data integrity.
**
The best way to explain what a stored procedure is, is to explain the legacy way of executing DB logic (ie not using a Stored Procedure).
The legacy way of creating systems was to use a 'Passthrough Query' and possibly have triggers in the DB.
Pretty much anyone who doesn't use Stored Procedures uses a thing call a 'Passthrough Query'
With the modern convention of Stored Procedures, triggers became legacy along with 'Passthrough Queries'.
The advantages of stored procedures are:
They can be cached as the physical text of the Stored Procedure
never changes.
They have built in mechanisms against malicious SQL
injection.
Only the parameters need be checked for malicious SQL
injection saving a lot of processor overhead.
Most modern database
engines actually compile Stored Procedures.
They increase the
degree of abstraction between tiers.
They occur in the same
process as the database allowing for greater optimisation and
throughput.
The entire workflow of the back end can be tested
without client side code. (for example the Execute command in
Transact SQL or the CALL command in MySQL).
They can be used to
enhance security because they can be leveraged to disallow the
database to be accessed in a way that is inconsistent with how the
system is designed to work. This is done through the database user
permission mechanism. For example you can give users privileges only
to EXECUTE Stored Procedures rather that SELECT, UPDATE etc
privileges.
No need for the DML layer associated with triggers. **
Using so much as one trigger, opens up a DML layer which is very
processor intensive **
In summary when creating a new SQL database system there is no good excuse to use Passthrough Queries.
It is also noteworthy to mention that it is perfectly safe to use Stored Procedures in legacy systems that already uses triggers or Passthrough Queries; meaning that migration from legacy to Stored Procedures is very easy and such migration need not take a system down for long if at all.
create procedure <owner>.<procedure name><param> <datatype>
As
<body>
Stored procedure are groups of SQL statements that centralize data access in one point. Useful for performing multiple operations in one shot.