Business Rules -&&> Using Lots Of UDFs && Views
Sep 7, 2007
I am in the process of building my first "large scale" database system (after 15+ years of developing Windows Apps and Web Apps) - so I am very VERY "Green" when it comes to Database development & SQL et al.
A little context setting: I am building a multi-tier Statistical Analysis & Reporting system where the "end product" will be Reports created in Reporting Services. There are a ton of business rules that I am implementing in a Business Logic Tier (hidden from the "end user" by a Data Access Tier) comprised of SQL in the form of UDFs (scalar) and Views.
The question: I have been reading that UDFs cause a performance hit compared to things like in-line functions. Alot of the Rules (implemented as Scalar UDFs) build on each other so that the output of UDF #1 is used as input to UDF #2.
So far I am implementing the Business Logic as a hierarchy of Views (7 Views to be exact) with each view implementing multiple Rules; each Rule basically a Scalar UDF. Below is an example of what I am doing:
Example
View #1 -> Select A, B, C, funcX1(A) as ValueX1, funcY1(B, C) as ValueY1 FROM someView
Then
View #2 -> Select A, B, C, ValueX1, ValueY1, funcX2 (ValueX1) as ValueX2, funcY2(ValueY2) as ValueY2 FROM View#1
Currently I have a hierarchy of 7 views that each use UDFs to implement the Business Rules, where the value calculated from a UDF in one View is used as input to UDF in a View further down the Hierarchy.
Is there a better way of implementing all of the Rules instead of using multiple Views with a bunch of UDFs?
The "end product" dataset is then exposed as a Stored Procedure to the reports in Reporting Services.
Any help would be GREATLY appreciated.
Thanks!
- marty
View 5 Replies
ADVERTISEMENT
Aug 15, 2006
I know there is a lot of information already out there on this topic,but given the following scenario...--------------------------------------------------------------------------------------------------------------------------------------Create a view like so ( pardon the pseudo-code )...CREATE View vwContactAddressesSelect * FROM Contact INNER JOIN Address ON Contact.ContactID =Address.ContactIDAnd then do a sargable select from the view using a stored procedureCREATE STORED PROCEDURE spSelect_ContactAddresses@ContactID intASSelect * FROM vwContactAddresses WHERE ContactID = @ContactID--------------------------------------------------------------------------------------------------------------------------------------In my understanding, "vwContactAddresses" would be substituted with theactual SQL join statement when the view is accessed.So for the stored procedure in question an execution plan for"Select * FROM Contact INNER JOIN Address ON Contact.ContactID =Address.ContactID WHERE ContactID = @ContactID" would be cached.Correct?With regards to execution plan caching, is this not the same ascreating an inline UDF that takes parameters or just creating a storedprocedure that would do the join w/out the view reference?
View 3 Replies
View Related
Aug 8, 2007
Which is the best practice for Business Rules
a. Hardcoded Column Names
b. Rowwise values RuleName, Criteria
Please suggest the best method
View 4 Replies
View Related
May 30, 2006
Hi All,
I'm pretty new to SQL Server 2005 and I'm wondering how to organize my
business rules efficiently.
I'm willing to create a Package with several Data Flow Task in my
Control Flow, each Business Rule will be encapsulated in a Data Flow
task. I guess this is possible in SSIS but I can't find how my data can
be send from one data flow to another one. I definitly don't want my
dataset to be parsed completly for each business rule.
Does anyone have an idea how to implement this in SSIS?
Kind regards,
Sébastien.
View 3 Replies
View Related
Jun 6, 2007
Similar to the BizTalk Business Rules engine does the SSIS provide any support for independent business rule management?
I would guess that through the use of Embedded CLR we can invoke the Business rules stored in the Business Rules Engine (either Biztalk Rule Engine or ILOG Rule Engine). Is there a construct in the SSIS similar to the BizTalk Call Rules Construct in the Biztalk Orchestration.
If this mechanism is not the preferred mechanism then are there any other mechanisms offered by SSIS which facilitate the use of Business Rule Engine Components within SSIS which make it easier to manage the business rules outside of the deployment.
Thanks
View 5 Replies
View Related
Oct 11, 2007
Hi,
We are planning to use the BTS BRE for our business rules and calling these from a data flow transformation (e.g. for every row in a flat file during import). One way would be to use a script component.
However, the question is that the script component would have to create and destroy BRE objects (e.g. a BRE Policy object) for every row in the flat file.
Is there a way to instantiate objects and whole on to them for the lifetime of the package or a container within a package?
Any suggestions regarding achieving the above most efficiently would be much appreciated.
Regards,
TD
View 3 Replies
View Related
Oct 23, 2007
Does anyone have a successful prescribed sequence for installing VS2005 and Business Intelligence Reports Projects on a Vista Business workstation to be used to create reports for a server?
I've looked through everything I can find here and I don't seem to see a clear solution without a lot of trial and error.
Fact is, I've not been successful getting just the reports to install on a plain XP box. Of course, the report creation looks fine on the server but I don't want to work directly on the server.
Thank you
View 1 Replies
View Related
Jun 10, 2006
Can anyone take me through synchronization of contacts within Business Contacts Outlook into Microsoft Small Business Accounts?
I run a stand alone PC with NO network. When SBA came SQL was also installed. Apparently you can synchronise Contacts within Business Contacts with SBA but both SBA & Outlook should work through the same SQL server.
Has anyone tried this?
Can someone walk me through the process?
Thanks
Debbie
View 1 Replies
View Related
Jun 6, 2006
How would I go about tracing UDF performance in profiler? I'd like to
specifically know the impact of the UDF without having to dig into the
execution plan of the statement containing it. Is this possible?
View 1 Replies
View Related
Aug 2, 2007
Can changes made to replicated stored procedures (and User-defined Functions) on the Publisher update the Subscriber database?
If I ALTER a SP (or UDF) on Database1 with peer-to-peer Transaction Replication to Database2, will the alter replicate to the Subscriber(s)?
Thomas
ThomBeaux
View 10 Replies
View Related
Jul 8, 2004
Hi,
What is the difference between a computed column and a UDF?
Is a computed column the same as the "Formula" field under Design Table in Enterprise Manager?
Also, what is the proper syntax for the Formula field? Can I use regular SQL on it or is there more to it?
thanks,
Frank
View 1 Replies
View Related
Jun 17, 2005
-- Author: Igor Nikiforov, Montreal, EMail: udfs@sympatico.ca
-- GETWORDCOUNT() User-Defined Function Counts the words in a string.
-- GETWORDCOUNT(@cString[, @cDelimiters])
-- Parameters
-- @cString nvarchar(4000) - Specifies the string whose words will be counted.
-- @cDelimiters nvarchar(256) - Optional. Specifies one or more optional characters used to separate words in @cString.
-- The default delimiters are space, tab, carriage return, and line feed. Note that GETWORDCOUNT( ) uses each of the characters in @cDelimiters as individual delimiters, not the entire string as a single delimiter.
-- Return Value smallint
-- Remarks GETWORDCOUNT() by default assumes that words are delimited by spaces or tabs. If you specify another character as delimiter, this function ignores spaces and tabs and uses only the specified character.
-- If you use 'AAA aaa, BBB bbb, CCC ccc.' as the target string for dbo.GETWORDCOUNT(), you can get all the following results.
-- declare @cString nvarchar(4000)
-- set @cString = 'AAA aaa, BBB bbb, CCC ccc.'
-- select dbo.GETWORDCOUNT(@cString, default) -- 6 - character groups, delimited by ' '
-- select dbo.GETWORDCOUNT(@cString, ',') -- 3 - character groups, delimited by ','
-- select dbo.GETWORDCOUNT(@cString, '.') -- 1 - character group, delimited by '.'
-- See Also GETWORDNUM() User-Defined Function
-- UDF the name and functionality of which correspond to the same built-in function of Visual FoxPro
CREATE function GETWORDCOUNT (@cSrting nvarchar(4000), @cDelimiters nvarchar(256) )
returns smallint
as
begin
-- if no break string is specified, the function uses spaces, tabs and line feed to delimit words.
set @cDelimiters = isnull(@cDelimiters, space(1)+char(9)+char(10))
declare @p smallint, @end_of_string smallint, @wordcount smallint
select @p = 1, @wordcount = 0
select @end_of_string = 1 + datalength(@cSrting)/(case SQL_VARIANT_PROPERTY(@cSrting,'BaseType') when 'nvarchar' then 2 else 1 end) -- for unicode
while dbo.CHARINDEX_BIN(substring(@cSrting, @p, 1), @cDelimiters, 1) > 0 and @end_of_string > @p -- skip opening break characters, if any
set @p = @p + 1
if @p < @end_of_string
begin
set @wordcount = 1 -- count the one we are in now count transitions from 'not in word' to 'in word'
-- if the current character is a break char, but the next one is not, we have entered a new word
while @p < @end_of_string
begin
if @p +1 < @end_of_string and dbo.CHARINDEX_BIN(substring(@cSrting, @p, 1), @cDelimiters, 1) > 0 and dbo.CHARINDEX_BIN(substring(@cSrting, @p+1, 1), @cDelimiters, 1) = 0
select @wordcount = @wordcount + 1, @p = @p + 1 -- Skip over the first character in the word. We know it cannot be a break character.
set @p = @p + 1
end
end
return @wordcount
end
GO
-- Author: Igor Nikiforov, Montreal, EMail: udfs@sympatico.ca
-- GETWORDNUM() User-Defined Function
-- Returns a specified word from a string.
-- GETWORDNUM(@cString, @nIndex[, @cDelimiters])
-- Parameters @cString nvarchar(4000) - Specifies the string to be evaluated
-- @nIndex smallint - Specifies the index position of the word to be returned. For example, if @nIndex is 3, GETWORDNUM( ) returns the third word (if @cString contains three or more words).
-- @cDelimiters nvarchar(256) - Optional. Specifies one or more optional characters used to separate words in @cString.
-- The default delimiters are space, tab, carriage return, and line feed. Note that GetWordNum( ) uses each of the characters in @cDelimiters as individual delimiters, not the entire string as a single delimiter.
-- Return Value nvarchar(4000)
-- Remarks Returns the word at the position specified by @nIndex in the target string, @cString. If @cString contains fewer than @nIndex words, GETWORDNUM( ) returns an empty string.
-- See Also
-- GETWORDCOUNT() User-Defined Function
-- UDF the name and functionality of which correspond to the same built-in function of Visual FoxPro
CREATE function GETWORDNUM (@cSrting nvarchar(4000), @nIndex smallint, @cDelimiters nvarchar(256) )
returns nvarchar(4000)
as
begin
-- if no break string is specified, the function uses spaces, tabs and line feed to delimit words.
set @cDelimiters = isnull(@cDelimiters, space(1)+char(9)+char(10))
declare @i smallint, @j smallint, @p smallint, @q smallint, @qmin smallint, @end_of_string smallint, @LenDelimiters smallint, @outstr nvarchar(4000)
select @i = 1, @p = 1, @q = 0, @outstr = ''
select @end_of_string = 1 + datalength(@cSrting)/(case SQL_VARIANT_PROPERTY(@cSrting,'BaseType') when 'nvarchar' then 2 else 1 end) -- for unicode
select @LenDelimiters = datalength(@cDelimiters)/(case SQL_VARIANT_PROPERTY(@cDelimiters,'BaseType') when 'nvarchar' then 2 else 1 end) -- for unicode
while @i <= @nIndex
begin
while dbo.CHARINDEX_BIN(substring(@cSrting, @p, 1), @cDelimiters, 1) > 0 and @end_of_string > @p -- skip opening break characters, if any
set @p = @p + 1
if @p >= @end_of_string
break
select @j = 1, @qmin = @end_of_string -- find next break character it marks the end of this word
while @j <= @LenDelimiters
begin
set @q = dbo.CHARINDEX_BIN(substring(@cDelimiters, @j, 1), @cSrting, @p)
set @j = @j + 1
if @q > 0 and @qmin > @q
set @qmin = @q
end
if @i = @nIndex -- this is the actual word we are looking for
begin
set @outstr = substring(@cSrting, @p, @qmin-@p)
break
end
set @p = @qmin + 1
if (@p >= @end_of_string)
break
set @i = @i + 1
end
return @outstr
end
GO
-- Is similar to the built-in function Transact-SQL charindex, but regardless of collation settings,
-- executes case-sensitive search
-- Author: Igor Nikiforov, Montreal, EMail: udfs@sympatico.ca
CREATE function CHARINDEX_BIN(@expression1 nvarchar(4000), @expression2 nvarchar(4000), @start_location smallint = 1)
returns nvarchar(4000)
as
begin
return charindex( cast(@expression1 as nvarchar(4000)) COLLATE Latin1_General_BIN, cast(@expression2 as nvarchar(4000)) COLLATE Latin1_General_BIN, @start_location )
end
GO
View 20 Replies
View Related
Mar 6, 2007
Hi!I need to refresh an entire database.I can recompile SPs with sp_recompile (or DBCC FLUSHPROCINDB), andrefresh views with sp_refreshView, but I cannot find any way torefresh my user-defined functions (some of them are like views, withparameters).Any help appreciated :) !Ben
View 5 Replies
View Related
Jan 28, 2004
Hi,
I have written an udf that checks for validations of an email address and returns 0 / 1 as per the validations. I came across an artical on MSDN that describes the steps to make my own system udf. http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnsqlpro01/html/sql01l1.asp
with help of that artical, I made my udf as a system udf. and now I can use it as follows.
select * , fn_isvalidemail(email) from #tp
now, I wanted to use this as a declarative check constraints in my tables. so I tried
create table testtable
( email_addr varchar (255) null CONSTRAINT CK_email_chk CHECK ( fn_isvalidemail(email) = 1) )
although this is syntax is logically correct, it does not get compiled
it gives me an error saying,
Server: Msg 195, Level 15, State 10, Line 2
'fn_isvalidemail' is not a recognized function name.
the strange part is that i made the function as another normal udf, It works in declarative constraints.
create table testtable
( email varchar (255) null CONSTRAINT CK_1p12 CHECK ( dbo.isvalidemail(email) = 1) )
Any thoughts on this ?
- Amit
View 2 Replies
View Related
Jun 9, 2015
I have always learn that UDFs are not Pre-Compiled while Stored procedures are. But I always had this questions why are UDFs are not Pre-Compiled.
I searched online for the answer but dint get an concrete justification on the same.
View 3 Replies
View Related
Feb 25, 2008
Hello,
How can I call UDFs on linked servers in SQL Server 2005?
More details:
I have some UDFs on Instance "VAXPServerA" in Database "DB1", for example "getSomething(number)".
It might look like this (for example):
----
CREATE FUNCTION [dbo].[getSomething] (
@theNumber int
)
RETURNS int AS
BEGIN
DECLARE @result int
SET @result = theNumber * 5
RETURN @result
END
----
I can call this function inside of the DB by typing:
----
SELECT dbo.getSomething(5)
----
I also can call the function from another DB on instance "VAXPServerA" by typing:
----
SELECT DB1.dbo.getSomething(5)
----
I have a second instance called "VAXPServerB", and "VAXPServerA" is a linked server in "VAXPServerB". I can do selects and stuff, it works fine.
But when I want to call the function...
----
SELECT [VAXPServerA].DB1.dbo.getSomething(5)
----
I obtain the next error:
Msg. 207, Level 16, State 1, Line 1
The column name 'VAXPServerA' is not valid.
Any hint?
Thanks in advance
David
View 1 Replies
View Related
Jul 23, 2005
I have a bunch of SPs that all rely on a UDF that parses a commadelimitted list of numbers into a table. Everything was working fine,but now my application is growing and I'm starting to approach the 8000character limit of the varChar variable used to store the list.I would like to change the UDF only and avoid having to dig through allof my stored procedures. I was hoping to use the text datatype toallow for much larger lists, but I am unable to perform anymanipulations necessary to parse the list into a table. I have triedPATINDEX, but it alone is not enough without the text maniuplations andI don't think the sp_xml_preparedocument can be used in a UDF.Anyone with any thoughts on managing large arrays in t-sql?thanks,Matt Weiner
View 2 Replies
View Related
Jul 20, 2007
Hello Folks,I encountered a problem with SQL server 2000 and UDFs.I have a scalar UDF and a table UDF where I would like the scalar UDFto provide the argument for the table UDF like in:SELECT*FROMtransaction_tWHEREtrxn_gu_id in (select get_trxns_for_quarter(get_current_quarter( GetDate() ) ))'get_current_quarter' returns an integer which is a GUID in a tablecontaining business quarter definitions, like start date, end date.'get_current_quarter' is a scalar UDF.'get_trxns_for_quarter' will then get all transctions that fall intothat quarter and return their GUID's in a table.'get_trxns_for_quarter' is a table UDF.This doesn't seem to work at all. Regardless whether I provide thenamespace (schema) calling the scalar UDF or not. Error message isjust different.Both functions operate correctly invoked un-nested.The whole expression does work fine if I turn 'get_trxns_for_quarter'into a scalar UDF as well, e.g. by returning just one trxn_gu_id withe.g. MAX() in a scalar datatype. But of course that's no good to me.It also works fine if I select the result of 'get_current_quarter'into a variable and pass that variable into 'get_trxns_for_quarter'.But that's no good to me either since then I cannot use the wholething embedded into other SELECT clauses.Both UDF's are non-deterministic but I couldnt see how that would havean impact anyway.Never mind the syntax on that example or anyhting, I tried all theobvious and not so obvious stuff and it really seems to come down tothe fact that one UDF is scalar and the other one is not. However, Idid not come across any type of information saying that this cannot bedone.Have you any ideas?Any help would be greatly appreciated.Carsten
View 6 Replies
View Related
Jul 20, 2005
There is something very strange going on here. Tested with ADO 2.7 andMSDE/2000. At first, things look quite sensible.You have a simple SQL query, let's sayselect * from mytab where col1 = 1234Now, let's write a simple VB program to do this query back to anMSDE/2000 database on our local machine. Effectively, we'llrs.open sSQLrs.closeand do that 1,000 times. We wont bother fetching the result set, itisn't important in this example.No problem. On my machine this takes around 1.6 seconds and modifyingthe code so that the column value in the where clause changes eachtime (i.e col1 = nnnn), doesn't make a substantial difference to thistime. Well, that all seems reasonable, so moving right along...Now we do it with a stored procedurecreate procedure proctest(@id int)asselect * from mytab where col1 = @idand we now find that executingproctest nnnn1,000 times takes around 1.6 seconds whether or not the argumentchanges. So far so good. No obvious saving, but then we wouldn'texpect any. The query is very simple, after all.Well, get to the point!Now create a table-returning UDFcreate function functest(@id int) returns table asreturn(select * from mytab where col1 = @id)try calling that 1,000 times asselect * from functest(nnnn)and we get around 5.5 seconds on my machine if the argument changes,otherwise 1.6 seconds if it remains the same for each call.Hmm, looks like the query plan is discarded if the argument changes.Well, that's fair enough I guess. UDFs might well be more expensive...gotta be careful about using them. It's odd that discarding the queryplan seems to be SO expensive, but hey, waddya expect?. (perhaps theUDF is completely rebuilt, who knows)last test, then. Create an SP that calls the UDFcreate procedure proctest1(@id int)asselect * from functest(@id)Ok, here's the $64,000 question. How long will this take if @idchanges each time. The raw UDF took 5.5 seconds, remember, so thisshould be slightly slower.But... IT IS NOT.. It takes 1.6 seconds whether or not @id changes.Somehow, the UDF becomes FOUR TIMES more efficient when wrapped in anSP.My theory, which I stress is not entirely scientific, goes somethinglike this:-I deduce that SQL Server decides to reuse the query plan in thiscircumstance but does NOT when the UDF is called directly. This iscounter-intuitive but it may be because SQL Server's query parser istuned for conventional SQL i.e it can saywell, I've gotselect * from mytab WHERE [something or other]and now I've gotselect * from mytab WHERE [something else]so I can probably re-use the query plan from last time. (I don't knowif it is this clever, but it does seem to know when twotextually-different queries have some degree of commonality)Whereas withselect * from UDF(arg1)andselect * from UDF(arg2)it goes... hmm, mebbe not.... I better not risk it.But withsp_something arg1andsp_something arg2it goes... yup, i'll just go call it... and because the SP was alreadycompiled, the internal call to the UDF already has a query plan.Anyway, that's the theory. For more complex UDFs, by the way, theperformance increase can be a lot more substantial. On a big complexUDF with a bunch of joins, I measured a tenfold increase inperformance just by wrapping it in an SP, as above.Obviously, wrapping a UDF in an SP isn't generally a good thing; theidea of UDFs is to allow the column list and where clause to filterthe rowset of the UDF, but if you are repeatedly calling the UDF withthe same where clause and column list, this will make it a *lot*faster.
View 3 Replies
View Related
Oct 7, 2015
We have migrated a database (myDb2014) to a SQL Server 2014 instance. We have another on a 2008R2 instance (myDb2008). Both on the same server.
I have setup a linked server to the 2014 instance from the 2008R2 one.
I have a number of sprocs on myDb2008 that call TVFs and sprocs on myDb2014. This worked fine when they were both on the same instance.
Now however, I have an issue where I would have to update all the references in each calling query.
I looked into creating Synonyms but this only works for Tables/Views.
Is there a workaround to querying myDb2014 TVFs/sprocs without having to update each calling query in myDb2008?
View 25 Replies
View Related
Jun 12, 2006
How can I list the stored procedures and user-defined functions that reference a given column? I could search ROUTINE_DEFINITION in INFORMATION_SCHEMA.ROUTINES for '%MyColumnName%' but MyColumnName is not always unique.
Thanks.
View 14 Replies
View Related
Apr 3, 2006
Fellow database developers,I would like to draw on your experience with views. I have a databasethat includes many views. Sometimes, views contains other views, andthose views in turn may contain views. In fact, I have some views inmy database that are a product of nested views of up to 6 levels deep!The reason we did this was.1. Object-oriented in nature. Makes it easy to work with them.2. Changing an underlying view (adding new fields, removing etc),automatically the higher up views inherit this new information. Thismake maintenance very easy.3. These nested views are only ever used for the reporting side of ourapplication, not for the day-to-day database use by the application.We use Crystal Reports and Crystal is smart enough (can't believe Ijust said that about Crystal) to only pull back the fields that arebeing accessed by the report. In other words, Crystal will issue aSelect field1, field2, field3 from ReportingView Where .... eventhough "ReportingView" contains a long list of fields.Problems I can see.1. Parent views generally use "Select * From childview". This meansthat we have to execute a "sp_refreshview" command against all viewswhenever child views are altered.2. Parent views return a lot of information that isn't necessarilyused.3. Makes it harder to track down exactly where the information iscoming from. You have to drill right through to the child view to seethe raw table joins etc.Does anyone have any comments on this database design? I would love tohear your opinions and tales from the trenches.Best regards,Rod.
View 15 Replies
View Related
Nov 29, 2007
(From an exchange originally posted on SQLServer.com, which wasn't resolved...)
To return views tailored to the user, I have a simple users table that holds user IDs, view names, parameter names, and parameter values that are fetched based on SUSER_SNAME(). The UDF is called MyParam, and takes as string arguments, the name of the view in use, and a parameter name. (The view the user sees is really a call to a corresponding table returning UDF, which accepts some parameters corresponding to the user.)
But the performance is very dependent on the nature of the function call. Here are two samples and the numbers reported by (my first use of) the performance monitor:
Call to table returning UDF, using local variables:
declare @orgauth varchar(50)
set @orgauth = dbo.MyParam('DeptAwards', 'OrgAuth')
declare @since datetime
set @since = DATEADD(DAY,-1 * dbo.MyParam('DeptAwards', 'DaysAgo'),CURRENT_TIMESTAMP)
select * from deptAwardsfn(@orgauth,@since)
[187 CPU, 16103 Reads, 187 Duration]
Call to same table returning UDF, using scalar UDFs in parameters:
SELECT *
from deptAwardsFn (
dbo.MyParam('DeptAwards', 'OrgAuth')
,DATEADD(DAY,-1 * dbo.MyParam('DeptAwards', 'DaysAgo'),CURRENT_TIMESTAMP)
)
[20625 CPU, 1709010 Reads, 20632 Duration]
(My BOL documentation claims the CPU is in milliseconds and the Duration is in microseconds -- which I question.) Regardless of the unit of measure, it takes a whole bunch longer in the second case.
My only guess is that T-SQL is deciding that the parameter values (returned by dbo.MyParam) are nondeterministic, and continually reevaluates them somehow or other. (What ever happened to call by value?)
Can anyone shed some light on this strange (to me) behavior?
----- (and later, from me)---
(I have since discovered that the reference to CURRENT_TIMESTAMP in the function argument is the cause, but I suspect that is an error -- it should only capture the value of CURRENT_TIMESTAMP once, when making the function call IMHO.)
View 8 Replies
View Related
May 6, 2007
In case some of you have read my previous posts, you may be aware that I'm writing a webboard application as a replacement for the old one.The old one currently have approximately 50000 topics in the database, each has on average 10 replies (I just check recently. I though it was only 7000 topics).I need to provide paging and sorting feature to the topic list. But I can't just SELECT all of them and let GridView do the paging/sorting, right?I have been using stored procedures to store my SQL statement for several projects now. I know how to deal with the paging feature (ROW_NUMBER), but the sorting requires me to change to change the "ORDER BY" clause.1. Can somebody tell me how to change the ORDER BY clause in the stored procedure(s) at runtime? Or does anyone have other approach?
Currently I'm thinking about moving back from store procedures to hard-code SQL statements, and then modify/generate the SQL statement for each paging / sorting. But I've learn that stored procedures give more performance and security.2. According to the situation I provided, is it worth moving from stored procedures to hard-code SQL?I'm also using 3-tier architecture approach + OOP. But I reach a conflict in my thoughts. You see, according to OOP, I'm supposed to create classes that reflect the actual objects in the real-world, right? In my case the classes are "Board, Topic, Reply, ...." According to this and 3-tier approach, I intend to use ObjectDataSource as a bridge between Presentation Logic and Business Logic. But I wonder what my datasource class should return3. Should my data source class return data objects like1st approach[DataObject(True)]pubic class TopicDataSource{ public static Topic[] GetTopicList() { }}or should it return DataSet / DataTable / DataReader like2nd approach [DataObject(True)]public class TopicDataSource{ public static DataTable GetTopicList() {}}Personally I think approach 1 is more OOP and allow for more extendability, but approach 2 might be faster.4. If I go with approach 1, how should I control which property of my data objects is read-only after it's has been inserted/created? Can I just set my data object's property to be readonly? Or do I have to set it at page level (i.e. GridView-> Columns -> BoundField -> ReadOnly=True)? Or do I set it and the page level and write a code to throw an exception in the rare case the application / user try to change it's value? Or else?Please help. These questions slow me down for days now.If there's any concepts that I misunderstood, please tell me. I'm aware that I don't know as much as some of you.I will be extremely grateful to anyone who answer any of my questions.Thanks a lot.PS. For those who think my questions are stupid, I'm very, very sorry that I bother you.
View 3 Replies
View Related
Sep 19, 2006
Hello :)
I seem to have somehow got myself into a situation where I'm having to run the following SELECTs, one after another, on a single ASP page. This is not tidy. How can I join them all together so I get a single recordset returned with all my stats in different columns?
SELECT COUNT(*) FROM tblQuiz WHERE [q3] = '5 years +' OR [q3] = '2 - 4 years'
SELECT COUNT(*) FROM tblQuiz WHERE [q4] <> '' AND [q4] IS NOT NULL
SELECT COUNT(*) FROM tblQuiz WHERE [q5] = 'Unhappy'
SELECT COUNT(*) FROM tblQuiz WHERE [q6] = 'Yes'
SELECT COUNT(*) FROM tblQuiz WHERE [q7] = 'Yes'
SELECT COUNT(*) FROM tblQuiz WHERE [q8] <> '' AND [q8] IS NOT NULL
View 8 Replies
View Related
Jul 20, 2005
Hello all,I have a database in SQL Server that should save data from a CRM-likeapplication.The database consists of tables like products, services, customers,partners etc. Problem is that the users should be able to find theseitems on different properties and with or without substring finding(SQL: LIKE). Example: I want the users to be able to find a customer,providing a customerID, but also providing a customername, zipcode orjust a part of those strings.This will result in a lot of queries. I bet there are some nicesolutions to this, since I will not be the first with this situation.If anyone can help, please.Thank you in advance.Regards,Freek Versteijn
View 3 Replies
View Related
May 21, 2004
Apparently, deleting 7,000,000 records from a table of about 20,000,000 is not advisable. We were able to take orders at 8:00AM, but not at 7:59.
So, what's the best way of going about deleting a large number of records? Pretty basic lookup table, no relationships with other tables, 12 or so address-type fields, 4 or 5 simple indexes. I can take it down for a weekend or night, if needed.
DTS the ones to keep to another table, drop the old and rename the new table?
Bulk copy out, truncate and bring back in?
DTS to text, truncate and import back?
Other ways?
Never worked with such a large table and need a little experienced guidance.
Thanks for the help
View 1 Replies
View Related
May 25, 2004
I am planning an application where ~1000 companies will be accessing data. Should I use a key to identify the company and place all data in one table i.e (WHERE company =123) or should the application create company specific tables i.e should I have 1000 small tables with 100 records in each, or one table with 100,000 records?
View 2 Replies
View Related
May 7, 2008
Hi,
You know how there are lots of hosted applications out there, many of them provide you with your own database (not shared).
1. If a server has 1K databases on it, will this slow down the server just due to the # of databases? (each user has their own database, but they won't be accessing it that much really).
A seperate database is required for security purposes usually.
2. Can you still open up EM with 1K+ databases?
View 3 Replies
View Related
Jan 30, 2007
Hi all,
I have a strange situation. Performance monitor shows that SQLServer:Transactions Transactions value is 125, but SQL Server Profiler does not show any activity.
I ran sp_who2 and I have a bunch of processes with SUSPENDED status. Would those be counted in Performance monitor?
When does a transaction get suspended?
Thanks.
Alec
View 1 Replies
View Related
Sep 20, 2007
I used MS SQL Server Management Studio Express to back up my SQL Server 2005 database called "PMDB" on a server in my office to a jump drive. Then, I removed the jump drive from the server and plugged it into my laptop. I then tried using MS SQL Server Management Studio Express to restore "PMDB" to my laptop SQL Server 2005 Express Edition (instance "Primavera") to a database called "pmdb$primavera". I've had several issues:
1. pmdb$primavera is now "locked up" "in the middle of a restore". I can't seem to unlock it even by rebooting my laptop.
2. when I execute the restore (I've used several command sequences...) I get a message that there are additional "families" restore is waiting for. I don't understand that.
3. I tried restoring to a completely new database (in the same instance...), but got the "family" problem. The query just hangs forever. When I cancel it, it hangs the database (see #1).
4. I now have two databases in the "Primavera" instance on my laptop in the "restoring" state. I can't get to either one of them.
I'm desperate. I have a customer presentation on Thursday where I must have the database working. Help!
Here's one of the queries I executed.... though I tweaked items here and there for 3 and 4 above.
restore database pmdb
from disk='f:databasebackupPMDB-BAK.BAK'
with recovery,
move 'pmdb_Dat' to 'C:Program FilesMSSQLPrimaveraMSSQL.1MSSQLDATApmdb$primavera_DAT.MDF',
move 'pmdb_log' to 'C:Program FilesMSSQLPrimaveraMSSQL.1MSSQLDATApmdb$primavera_LOG.LDF'
go
The issue seems to be #2 above each time.
View 4 Replies
View Related
Nov 14, 2007
Every time a transaction log is dumped we see the following message in the log file:
BackupDiskFile:penMedia: Backup device '\s-sqlbkups-1g$myserverlogmy_databasemydatabase_backup_200711071430.trn' failed to open. Operating system error 2(The system cannot find the file specified.).
Source spid139
Message
Error: 18204, Severity: 16, State: 1.
And yet, the actual log dump appears fine and the file is found on the share. The dump is done with a maintenance plan.
Any ideas?
View 2 Replies
View Related
Sep 8, 2006
I have a page that has about 8 dropdown boxes that need to be populated from sql tables. What is the best way to populate these boxes. Here is how I have it nowconn = New SqlConnection(ConfigurationManager.AppSettings("SQLString")) ''''''''''''' Fill in DropDownList Status '''''''''''''''''''strSelect = "SELECT * FROM Requests_Status"cmdSelect = New SqlCommand(strSelect, conn) conn.Open()dtrSearch = cmdSelect.ExecuteReader()ddlRequestStatus.DataSource = dtrSearchddlRequestStatus.DataTextField = "RequestStatusName"ddlRequestStatus.DataValueField = "RequestStatus"ddlRequestStatus.DataBind()ddlRequestStatus.Items.Insert(0, New ListItem("-- Select Below --", -1)) cmdSelect.Cancel()dtrSearch.Close()conn.Close()''''''''''''' Fill in DropDownList Container '''''''''''''''''''strSelect = "SELECT * FROM Containers"cmdSelect = New SqlCommand(strSelect, conn) conn.Open()dtrSearch = cmdSelect.ExecuteReader()ddlContainer.DataSource = dtrSearchddlContainer.DataTextField = "ContainerName"ddlContainer.DataValueField = "ContainerID"ddlContainer.DataBind()ddlContainer.Items.Insert(0, New ListItem("-- Select Below --", -1)) cmdSelect.Cancel()dtrSearch.Close()conn.Close()'''''''''''''''''''''''''''''I then repeat the same commands as above for the other 6 dropdowns. This seems like a bad way to have to do all this.ThanksCraig
View 3 Replies
View Related
