Showing posts with label writing. Show all posts
Showing posts with label writing. Show all posts

Wednesday, March 28, 2012

IF ELSE with WHERE, AND, OR

What would be the correct way of writing a sql select state with where
clause while also using IF ELSE. I am using T-SQL and I cannot get it
to work. I probably have the syntax wrong.

I want to be able to have different where/and/or clauses in the sql
dependant on what value was passed into the @.SearchTerm parameter in
this stored procedure.

Can I use CASE statements in the WHERE section? Or is that strickly for
SELECT statements?

Code as follows:

================================================== ==============

CREATE PROCEDURE spTicketReport
(
@.SearchTerm varchar(100) = NULL
)
AS
BEGIN
SELECT TOP 100 PERCENT Tickets.TicketID, Tickets.TicketNumber AS
TicketNumber, Haulers.Name AS Hauler, Leases.LeaseID AS LeaseID,
Leases.LeaseName AS Lease, Shippers.Name AS
Shipper, Tickets.FeeTox, Tickets.FeeWashout, Tickets.FeeDisposal,
Tickets.Yards, Tickets.Barrels,
Tickets.FluidSolidRatio, DATEPART(yyyy, Tickets.DateAdded) AS [Year]
FROM Tickets INNER JOIN
Leases ON Tickets.LeaseID = Leases.LeaseID INNER
JOIN
Haulers ON Tickets.HaulerID = Haulers.HaulerID
INNER JOIN
Shippers ON Tickets.ShipperID =
Shippers.ShipperID
WHERE TicketNumber LIKE '%' + @.SearchTerm + '%' OR Haulers.Name LIKE
'%' + @.SearchTerm + '%' OR Shippers.Name LIKE '%' + @.SearchTerm + '%'
OR Leases.LeaseName LIKE '%' + @.SearchTerm + '%'
ORDER BY TicketNumber, Shipper, Hauler

================================================== ==============

Thanks in advance!

Jason Cochran
Rethink Technologies, L.L.C.
www.rethinkllc.com(jcochran@.rethinkllc.com) writes:
> What would be the correct way of writing a sql select state with where
> clause while also using IF ELSE. I am using T-SQL and I cannot get it
> to work. I probably have the syntax wrong.
> I want to be able to have different where/and/or clauses in the sql
> dependant on what value was passed into the @.SearchTerm parameter in
> this stored procedure.
> Can I use CASE statements in the WHERE section? Or is that strickly for
> SELECT statements?

You cannot use CASE statements, because there are none in T-SQL. But
you can use CASE expressions in a WHERE clause:

WHERE CASE WHEN @.SearchTerm LIKE <a ticket number>
THEN TicketNumber LIKE '%' + @.SearchTerm + '%'
WHEN @.SearchTerm LIKE <a haluers name>
THEN Haulers.Name
ELSE Leases.LeaseName
END LIKE '%' + @.SearchTerm + '%'

--
Erland Sommarskog, SQL Server MVP, esquel@.sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp|||This is a good piece of information, however it can be achieved by the
other way as well...
By using parantheses and boolean operators (AND, OR, NOT) properly.

Something like this:

WHERE ( @.SearchTerm LIKE <a ticket number> ANDTicketNumber LIKE '%'
+ @.SearchTerm + '%' )
OR
( @.SearchTerm LIKE <a haluers name> ANDHaulers.Name LIKE '%' +
@.SearchTerm + '%' )
OR
( Leases.LeaseName LIKE '%' + @.SearchTerm + '%' )|||Hi Erland,
Very informative answer , but from performance point of view we should
not be using Like

Most DBMSs will use an index for a LIKE pattern if it starts with a
real character but will avoid an index for a LIKE pattern that starts
with a wildcard (either % or _). The only DBMSs that never use indexes
for LIKE are Pick and mSQL (on TEXT fields). For example, if the search
condition is:

... WHERE column1 LIKE 'C_F%'

DBMSs will resolve it by finding all index keys that start with C and
then filtering those that contain F in the third position. In other
words, you don't need to transform this search condition:
Here '%' is being used at the beginning so I think using charindex will
do fine job (Please correct it if wrong)

Wherecharindex
( @.SearchTerm,
(
CASE
WHEN charindex(@.SearchTerm, a ticket number )>0 THEN TicketNumber

WHEN charindex(@.SearchTerm,a haluers name) > 0 THEN Haulers.Name

ELSE Leases.LeaseName
END
)
)>0

With warm regards
Jatinder|||I appreciate everyones help on this.

What if I wanted to add another parameter named @.AccountID. AccountID
is used to track who created the ticket. @.AccountID would be set to
NULL just like @.SearchTerm is. I wanted to be able to check to see if
either was passed in. Sometimes both will be; other times it will be
either/or.

============ PSEUDO CODE ===================

WHERE TicketID != 0

IF NOT @.SearchTerm IS NULL THEN
AND (TicketNumber LIKE '%' + @.SearchTerm + '%' OR Haulers.Name
LIKE '%' + @.SearchTerm + '%' OR Shippers.Name LIKE '%' + @.SearchTerm +
'%' OR Leases.LeaseName LIKE '%' + @.SearchTerm + '%' )
END IF
IF NOT @.AccountID IS NULL THEN
AND AccountID = @.AccountID
END IF

ORDER BY TicketNumber, Shipper, Hauler

============ END PSEUDO CODE ===================|||(jcochran@.rethinkllc.com) writes:
> I appreciate everyones help on this.
> What if I wanted to add another parameter named @.AccountID. AccountID
> is used to track who created the ticket. @.AccountID would be set to
> NULL just like @.SearchTerm is. I wanted to be able to check to see if
> either was passed in. Sometimes both will be; other times it will be
> either/or.
>...
> IF NOT @.AccountID IS NULL THEN
> AND AccountID = @.AccountID
> END IF

AND (AccountID = @.AccountID OR @.AccountID IS NULL)

However, beware that if you want any index on AccuontID to be use, you
better split this up and have two different SELECT statements.

For a much longer discussion on a problem which you have not really
reached, but seem to be on your way to, I have an article on my web
site that you can save for a rainy day:
http://www.sommarskog.se/dyn-search.html.

--
Erland Sommarskog, SQL Server MVP, esquel@.sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp|||Looking at that article you mentioned; under if statements, the code
below is mentioned. It just seems like a very nasty way of doing
things. I could do it this way BUT I just think there should be a much
cleaner way of doing it. If I had to change/remove/add a column in the
select statement, I would have 3 other places to do it in. The WHERE
statement should be the only thing that is different. I shouldnt have
to have the same select statement 3 times.

IF @.orderid IS NOT NULL
BEGIN
SELECT ...
WHERE o.OrderID = @.orderid
AND od.OrderID = @.orderid
AND (od.UnitPrice >= @.minprice OR @.minprice IS NULL)
AND (od.UnitPrice <= @.maxprice OR @.maxprice IS NULL)
AND (od.ProductID = @.prodid OR @.prodid IS NULL)
AND (p.ProductName LIKE @.prodname + '%' OR @.prodname IS NULL)
ORDER BY o.OrderID
END
ELSE IF @.custid IS NOT NULL
BEGIN
SELECT ...
WHERE (o.OrderDate >= @.fromdate OR @.fromdate IS NULL)
AND (o.OrderDate <= @.todate OR @.todate IS NULL)
AND (od.UnitPrice >= @.minprice OR @.minprice IS NULL)
AND (od.UnitPrice <= @.maxprice OR @.maxprice IS NULL)
AND c.CustomerID = @.custid
AND o.CustomerID = @.custid
AND (od.ProductID = @.prodid OR @.prodid IS NULL)
AND (p.ProductName LIKE @.prodname + '%' OR @.prodname IS NULL)
ORDER BY o.OrderID
END
ELSE
BEGIN
SELECT ...
WHERE (o.OrderDate >= @.fromdate OR @.fromdate IS NULL)
AND (o.OrderDate <= @.todate OR @.todate IS NULL)
AND (od.UnitPrice >= @.minprice OR @.minprice IS NULL)
AND (od.UnitPrice <= @.maxprice OR @.maxprice IS NULL)
AND (c.CompanyName LIKE @.custname + '%' OR @.custname IS NULL)
AND (c.City = @.city OR @.city IS NULL)
AND (c.Region = @.region OR @.region IS NULL)
AND (c.Country = @.country OR @.country IS NULL)
AND (od.ProductID = @.prodid OR @.prodid IS NULL)
AND (p.ProductName LIKE @.prodname + '%' OR @.prodname IS NULL)
ORDER BY o.OrderID
END|||jcochran@.rethinkllc.com (jcochran@.rethinkllc.com) writes:
> Looking at that article you mentioned; under if statements, the code
> below is mentioned. It just seems like a very nasty way of doing
> things.

This is indeed not a method that scales well in terms of maintenance
when you have many different conditions, and I also note this in the
article.

> I could do it this way BUT I just think there should be a much
> cleaner way of doing it. If I had to change/remove/add a column in the
> select statement, I would have 3 other places to do it in. The WHERE
> statement should be the only thing that is different. I shouldnt have
> to have the same select statement 3 times.

Well, it depends with you mean with cleaner. You can do all in one
single static SQL statement, and from the perspective of maintenance
and functionality you would be fine. However, SQL programming is also
a lot about performance. If your table has 100 million rows, you don't
want a table scan to happen on an interactive query.

For this reason, one sometimes has to duplicate code in a way that
conflicts with the best practices you've learnt when working with
traditional languages.

--
Erland Sommarskog, SQL Server MVP, esquel@.sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp

Monday, March 26, 2012

IF Command

Hi All,

I am having a few problems writing a sp for the sales team, I have to display a target figure from a customer dates

start_date target_year1 target_year2 target_year3 target_year4 target_year5 01/01/2004 100 150 120 150 170 01/01/2003 90 20 30 30 30

the start date for each customer is different so the target year 1 ,2 ect will be different time periods.

i need to display the start_date and the target year which relates to todays date:

so no 1 would be year 3 and no2 will be year 4.

any help would be much needed!!

rich

Hi,

To do this you can use case statements.

try this:

select startdate, case datediff(yy, startdate, getdate())

when 0 then targetyear1

when 1 then targetyear 2

.

.

etc

from yourtable

Regards

|||thanks for your help, worked a treat!|||

JMattias

sorry the example was not very good the month my change,

so I would change the yy for month...the next problem is in the selecting between months

select startdate, case datediff(mm, startdate, getdate())

when <12 then targetyear1

when >= 12 and < 24 then targetyear 2

ect..

But this does not work ......

|||

use the datediff statement in every when

Like this

select startdate, case when datediff...... then when datediff..... then etc

Regards

|||thanks ...now that did do the job!!|||Good, I'm glad to help!

Friday, March 9, 2012

Identity Increment

Hello, I need some help writing a script to generate Identity keys. I cannot use the row number generator because I would like to start the identity at a package level variable. Is this possible?
Thank you in advance

I just find this using a web search engine:

http://www.sqljunkies.com/WebLog/sqlbi/archive/2005/05/30/15684.aspx

I know that has been also discussed in this forum; I recommned you tu use the search functionality of the forum

|||http://www.ssistalk.com/2007/02/20/generating-surrogate-keys/