Doing Math Across Table Columns, Dealing With NULL
Oct 20, 2005
Christine the Pharmacist writes "Please pardon as I am not horribly advanced with SQL...
Using SQL Server 2000, Windows 2000, Service pack 4
I'm trying to figure out marketshares for "preferred" products. I have a table put together by hospital and month of medication use with the totals of each drug dispensed in columns as well.
(example table below)
Hospital Month Drug A Drug B Drug C Drug D
A 7 5 10 58 73
B 7 NULL 26 98 43
etc.
** Drug C and Drug D are the preferred drugs
I'm getting correct preferred % in all cases except when a value is NULL (result is NULL). I'm using an aggregate (sum), which should ignore NULLs, but it ignores NULLs within a column, and not ignoring across columns. I've tried setting concat_null_yields_null off and I'm still getting NULL (since I'm using the plus sign).
This is my admittedly confused select statement, suspect this is where my problem lies (problems with saying "sum", but using "+" as well?):
select a.Hospital,a.month,convert(float,sum(c.Drug_C+d.Drug_D))/convert(float,sum(a.Drug_A+b.Drug_B+
c.Drug_C+d.Drug_D)) as preferred_share
hi ive got a inert sub where i grab values from text boxes etxthe values are passed to a stored procedure however , one of these fields is a date field , but the field is not required ...so on this line if the date text box is left blank i get an error , not a valid date .Parameters.Add("@actiondate", SqlDbType.DateTime).Value = txtActionDate.Texti have tried ( the actiondate field can take nulls ..)if txtActionDate="" then .Parameters.Add("@actiondate", SqlDbType.DateTime).Value = nothing else.Parameters.Add("@actiondate", SqlDbType.DateTime).Value = txtActionDate.Textend if but this doesnt workwhat is the best way of allowing blank values to be passed to the stored procedure( it doesnt fall over with normal text / varchar fields ) thanks
I have a stored procedure as a recordsource from a contacts table. Inthis example, users can enter parameters to limit contacts by firstletter of last name or company name or keywords:Example:@myName nvarchar(30) = null,@Alpha char(1) = nullSELECTContacts.ContactID, ContactType,CASE WHEN Contacts.ContactType = 0THEN Contacts.CompanyNameELSEisNull(Contacts.LastName,'?') + ', ' +isNull(Contacts.FirstName,'?')ENDAS CNAMEFROMContactsWHERE(Keywords Like '%' + @myKeyword + '%' OR @myKeyword is Null)So far, so good, but...The problem is I want to also give the user the option of filteringalphabetically by first letter. I can't figure out how to deal withnulls in this example (user doesn't enter anything as parameter@Alpha):AND(@Alpha = CASE ContactType WHEN 0 THEN Left(LastName,1) ENDOR@Alpha = CASE ContactType WHEN 1 THEN Left(CompanyName,1) END)Any help is appreciated,LQ
Hi EveryoneVery new to .net and currently dipping my toes in the water with a small application, but getting to the point - I have a form which has somel text fields that expect a date but which are not a required field so in other words the user can leave them blank. The code behind page stores the information using a stored procedure which I add parameters to in the following fashion - SqlParameter userdate = new SqlParameter();userdate .ParameterName = "@dtdate";userdate .SqlDbType = SqlDbType.DateTime;userdate .Direction = ParameterDirection.Input;userdate .Value = dtdate.Text.ToString();cmd.Parameters.Add(userdate); Now if I leave the text field dtdate blank I receive an error because the above expects a date. If I remove the line userdate .SqlDbType = SqlDbType.DateTime; I don't recieve an error but my stored procedure saves the date as 01/01/1900 or similar. I believe this is because in my stored procedure the paramger dtdate is defined as @dtdate datetime Obviously I want to have it so that if the user leaves the text field empty then no date is saved in the database and was wondering how other people tackle this scenario.
Hi post a sample code create table testNull( a int not Null, b varchar(5), c varchar(5) )
insert into testNull (a,b,c) values(1,'Alex','test') insert into testNull (a,b) values(2,'Alex2')
1. select * from testNull -- return 2 rows 2. select * from testNull where a <> 3 and b <> 'C1' and c <>'C2' -- return ONLY 1 ROW !!! 3. select * from testNull where a <> 3 and b <> 'C1' and isNull(c,'') <>'C2'
query 2 will retun only 1 row, because value of column c is Null
Question Is any setting could be changed on db or server level to prevent errors with missing row in 2-nd query , or I have use isNull operator for every column acepting Null as value ?
Using a reporting services model/report builder we have two related tables: - Fundings, (parent) - Draws, (child)
Report Builder reports that subtract "Total Fundings.Amount", (which is SUM(FundingAmount)) from "Total Draw Amount", (which is SUM(DrawAmount)) to get a balance work as expected except when there are no Draw rows, in which case a NULL is returned. Obviously we want to convert NULL values of "Total Draw Amount" to zero so that when subtracted from "Total Fundings.Amount" the correct value is displayed. I've searched for a function similar to COALESCE (Transact-SQL) in report builder but found nothing.
Hello,Suppose I have the following table...name employeeId email--------------------------------------------Tom 12345 Join Bytes!Hary 54321Hary 54321 Join Bytes!I only want unique employeeIds return. If I use Distinct it will stillreturn all of the above as the email is different/missing. Is there away to query in SQL so that only distinct employeeId is returned? noduplicates.I wouuld like to say WHERE no blank fields are present to get theright row to return.Many thanksYas
I need help to build a query that shows me how many columns inside a range on columns are null. Example: quantity1;quantity2;quantity3;quantity4;quantity5; quantity6;quantity7;
Total amount = 1000 salemancode1 = space salemancode2 = Staff-99 salemancode3 = space salemancode4 = staff-88
How I can write a one query statement to do this, we expect to count how many salemancode is not space and count the number of salesman to over the total amount.
total amount / (no_of_saleman) as commission the result is 1000/ 2 the commission is $500.
Hi,I have some tables where I import data in, lots of field have gotten aNULL value which the application can not handle.Now can I replace each NULL value with '' in a columns with:update <tableset [<column>] = '' where [<column>] IS NULLBut because there are lots of columns this is pretty much work, alsothere are multiple tables.Is there an easy way to replace all NULL values in all columns in atable?Thanks in AdvanceBob
I am facing a problem on validating the data from a flat file while inserting the data into the destination table of sql server 2005 database. In my package, i have to validate the input data whether the values are coming as null or not, before inserting into the destination database. The flat file may not contain data for all NOT NULL columns. I have to find out that row(s) and reject the record. If the rows are coming as Null for the Not Null columns, the OLEDB Destination throws OLEDB exception for the constraint.
To resolve this, i have an script component in data flow, to check whether the input data is coming as null. I have added the output column of boolean type to the script component, it will be assigned to TRUE when there is null for the Not Null column in the script.
And in the follwing conditional split, i am checking the flag for TRUE to reject the record.
I have a excel sheet with some data and blank columns. I have a ssis package using to import data from excel to sql table. For blank excel columns it is importing as null instead i want to show them as '0'. If data comes in it should update the data.
I need to script out data in several tables (30+) and then reload those tables on a different database. The "target" database table data will get overwritten each time, not appended to. Several of these tables have numerous foreign keys and other constraints that must be dealt with. None of them have more than 100 records or so. Then I need to keep this script in source control and reference it as part of a post-deployment step with a Visual Studio DB project.
I have redgate, dbghost and visual studio. Are there any tools will generate the script for me complete with dropping all the constraints, truncating the tables, then re-adding the constraints back? Or, am I looking at simply scripting the table data out, then modifying the script myself to add in the steps to drop/readd the constraints? Further, since some of these tables might have relationships, not just to other tables, but to those in question, there will likely be an order in which the tables need to get loaded.
The approach I am thinking will be needed, since ive done this sort of thing before except with SSIS, is to run something like dbghost or the "generate scripts" option in SSMS as a starting point. From there, change the order around as needed, etc.
When I run:select * from testtableI get this error message:Invalid object name 'testtable'.However, if I run:select * from testuser.testtableIt works. I'm logged in as testuser, and testuser is the databaseobject owner and tableowner. This was a restored database from adifferent server in SQL Server 2000. The testuser login was in theprevious database. I created the same login in this new test databaseand made it database owner.I've also tried running: sp_change_users_login 'Update_One','testuser', 'testuser'It completed successfully but I still get:select * from testtableInvalid object name 'testtable'.I've also tried creating a different user and making it database ownerand when I change table object owner to this new user, I still get thesame problem. I need to specify:select * from newtestuser.testtableEven though I'm logged in as newtestuser.I also then tried changing table owner to dbo. This seems to worklogged in as either user, but I want to have the tables owned by theuser not dbo. How can I resolve this?Any help would be appreciated.Erin
I have two columns A (which allows nulls) and B( which does not allow nulls). How can I add the contents of columns A and B SO THAT I DO NOT GET A NULL RESULT WHEN A IS NULL.
The result of A+B concatanation will be stored in a column, C.
So I have been trying to get mySQL query to work for a large database that I have. I have (lets say) two tables Table_One and Table_Two. Table_One has three columns: Type, Animal and TestID and Table_Two has 2 columns Test_Name and Test_ID. Example with values is below:
In Table_One all types come under one column and the values of all Types (Mammal, Fish, Bird, Reptile) come under another column (Animals). Table_One and Two can be linked by Test_ID
I am trying to create a table such as shown below:
This should be my final table. The approach I am currently using is to make multiple instances of Table_One and using joins to form this final table. So the column Bird, Reptile, Mammal and Fish all come from a different copy of Table_one.
For e.g
Select Test_Name AS 'Test_Name', Table_Bird.Animal AS 'Birds', Table_Mammal.Animal AS 'Mammal', Table_Reptile.Animal AS 'Reptile, Table_Fish.Animal AS 'Fish' From Table_One
[Code] .....
The problem with this query is it only works when all entries for Birds, Mammals, Reptiles and Fish have some value. If one field is empty as for Test_Two or Test_Three, it doesn't return that record. I used Or instead of And in the WHERE clause but that didn't work as well.
ColumnA has existing data in it some of the data are Nulls what would be the best way to have new as well as existing data change to 0, using a constraint?
I have a flat file with 5 columns and in the table I have 30 columns and they all are (not null) I cannot leave other columns in target for which it throws mistake, have to insert something, since as I insert information in the demas columns???
If I had a basic table with 3 VARCHAR fields; let's say A, B, C
How could I write a query that returns the count of the number of NULL columns for every record in a table?
Ideally, it would be something like:
SELECT CAST (A IS NULL) AS INTEGER + CAST (B IS NULL) AS INTEGER + CAST (C IS NULL) AS INTEGER FROM MyTable
That doesn't work at all. I can't seem to do "IS NULL" in the SELECT area. Should I write a T-SQL user-defined function that takes all three columns as parameters? Would that be performance friendly for large data sets?
I am trying to create a stored procedure where.I need to loop through every row of the table and check if there exists a date in either of the column. If date exists in either of the column for every row, I need to update some other stuff.For the above table, it meets my requirement, so I need to update. However if the table is as below, it doesn't meet the requirement, so I don't need to update
johnny writes "I am trying to return only the columns from multiple tables that are NOT NULL for a specific ID. Once I have the tables JOINED is there a way to only get those columns that are populated. Thanks."
Using SQL2000. I want to return the # of columns with non-nullvalues. Here's my query so far:selectcase when Dx1 is not null then 0 else 1 end +case when Dx2 is not null then 0 else 1 end +case when Dx3 is not null then 0 else 1 end +case when Dx4 is not null then 0 else 1 end as DxCountfrom tblClerkshipDataCleanwhere PalmName = @PalmNameThere are 7 rows for the particular PalmName I'm using. The queryreturns a result of 7. However, there are 25 values in Dx1 thru Dx4so the query should be returning 25.What am I doing wrong here? Thanks in advance.
This question comes without the wish for any philosofical debates concerning NULL
Normally SQL Server 2005 uses 13 bytes to store a NUMERIC(22,7) value. Does it use the full 13 bytes when the column contains NULL as well? And what about DATETIME and (BIG)INT? Most of the info on storage of NULL values is about varchar/char/nvarchar/varchar...
I want to run a query that selects rows from the table where a datetime column has null values; select * from Orders where IsNull(dClosedDate,'Null') = 'Null' However i get this error: Conversion failed when converting datetime from character string. Any help appreciated
Ive created a Data Access Layer (xsd file) and some of the tables have DateTime columns. I need to allow NULL values to be saved, but when I try to do that I get an error In my code (c#) ive used Nullable DateTime, but when I try to assign a nullable Datetime to a DateTime column, I get this error cannot implicitly convert type 'System.DateTime?' to 'System.DateTime' I understand the reasons why, so how do I save null DateTime values to the underlying database through a schema ? In the schema file, the DateTime columns have <DBNULL> as the default value, AllowBDNull is true, but I am only allowed 'Throw exception' on the NULL value property I could probably do this another way (by not using a schema and writing the code myself) but Id prefer to keep the strongly typed code. I dont want to use MAx or MIn values for the default datetime values, so how can this be done ?
How to find out that there is a null value in a column rather than a valid integer, DateTime or bool value, for strings I use 'as' operator to cast the column value and it returns null when column value is null, but for value types using 'as' operator causes compile error and using simple casting causes runtime error, for example:
int count = (int)row["Count"];
and
int count = row["Count"] as int;
the first one throws an exception when Count is null and the second doesn't compile at all since 'as' applies to reference types, so what is the way other than exception handling to determine null value in a column?
parsename('$'+ Convert(varchar,Convert(money,Q.[Product Cost]-R.[Shared Cost]),1),2) as [Pre Cost], parsename('$'+ Convert(varchar,Convert(money,R.[New Product Cost]-R.[Shared Cost]),1),2) as [Post Cost]
Formula: [Post Cost] / [Pre Cost]
Expected:
If [Post Cost] is null then I would need to assign 1 and divide by [Pre Cost] and similarly if [Pre Cost] is null then I would need to assign 1 so that I can divide [Post Cost] / [Pre Cost]
Table DDL below:The tables I have contain Timesheet information. Each row in thetblTSCollected table contains an entry for an employee into thetimesheet system, specifically by scanning the barcode on their badge.A whole bunch of business logic periodically attempts to "pair" theseinto logically matched scans. For example, some employees will scan inand out of a single place of work. For these there will be a rowwritten to the tblTSRuleApplied table which contains, inter alia andsome redundant data, the fldCollectedID for the two rows. The earlierwill be put into the fldStartTimeCollectedID, and the later into thefldEndTimeCollectedID. Some employees will clock on at their base,then perform sub-duties at different locations during the day, andclock off at their home base at the end of their shift. For these, thesystem would identify the outer records as a matching pair, and thenpair up inner records by location.However, if the employee fails to enter a valid "clocking in and out"pair (for example, if they clock in at the wrong location) the systemneeds to generate a "dummy" "clocking in and out" record for thepayroll department. Ideally, this would have NULL values in thefldStartTimeCollectedID and fldEndTimeCollectedID columns. This wouldalert a user in a different part of the system, where missingtimesheets were being arbitrated, that an employee appeared to havefailed to clock in for that day. Of course, the user could seeon-screen that they had clocked in, but at an incorrect location.Unfortunately, the database designer is not here for the moment (he wasknocked off his bicycle recently), but he put a unique index on thetblTSRuleApplied table that prevents the same value being entered intothe fldStartTimeCollectedID and fldEndTimeCollectedID columns. This isgenerally A Good Thing, since we don't want the same timesheet scan toform both a "clocking on" event and a "clocking off" event.So, is there any way of retaining the requirement that thefldStartTimeCollectedID and the fldEndTimeCollectedID columns may notcontain the same value in a single row, UNLESS that value is NULL inwhich case all is hunky dory. I should add that the clients don't muchcare for Triggers (and neither do I for that matter).Many thanks if you are able to help.Edwardif exists (select * from dbo.sysobjects where id =object_id(N'[dbo].[FK_tblTSRuleApplied_tblTSCollected]') andOBJECTPROPERTY(id, N'IsForeignKey') = 1)ALTER TABLE [dbo].[tblTSRuleApplied] DROP CONSTRAINTFK_tblTSRuleApplied_tblTSCollectedGOif exists (select * from dbo.sysobjects where id =object_id(N'[dbo].[FK_tblTSRuleApplied_tblTSCollected1]') andOBJECTPROPERTY(id, N'IsForeignKey') = 1)ALTER TABLE [dbo].[tblTSRuleApplied] DROP CONSTRAINTFK_tblTSRuleApplied_tblTSCollected1GOif exists (select * from dbo.sysobjects where id =object_id(N'[dbo].[FK_tblTSArbAccept_tblTSRuleApplied]') andOBJECTPROPERTY(id, N'IsForeignKey') = 1)ALTER TABLE [dbo].[tblTSArbAccept] DROP CONSTRAINTFK_tblTSArbAccept_tblTSRuleAppliedGOif exists (select * from dbo.sysobjects where id =object_id(N'[dbo].[FK_tblTSCollected_tblTSRuleApplied]') andOBJECTPROPERTY(id, N'IsForeignKey') = 1)ALTER TABLE [dbo].[tblTSCollected] DROP CONSTRAINTFK_tblTSCollected_tblTSRuleAppliedGOif exists (select * from dbo.sysobjects where id =object_id(N'[dbo].[tblTSCollected]') and OBJECTPROPERTY(id,N'IsUserTable') = 1)drop table [dbo].[tblTSCollected]GOif exists (select * from dbo.sysobjects where id =object_id(N'[dbo].[tblTSRuleApplied]') and OBJECTPROPERTY(id,N'IsUserTable') = 1)drop table [dbo].[tblTSRuleApplied]GOCREATE TABLE [dbo].[tblTSCollected] ([fldCollectedID] [int] IDENTITY (1, 1) NOT NULL ,[fldEmployeeID] [int] NULL ,[fldLocationCode] [varchar] (50) COLLATE SQL_Latin1_General_CP1_CI_ASNULL ,[fldTimeStamp] [datetime] NULL ,[fldRuleAppliedID] [int] NULL ,[fldBarCode] [varchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NULL,[fldProcessed] [smallint] NOT NULL) ON [PRIMARY]GOCREATE TABLE [dbo].[tblTSRuleApplied] ([fldEmpRuleID] [int] NOT NULL ,[fldRuleAppliedID] [int] IDENTITY (1, 1) NOT NULL ,[fldStartTime] [datetime] NULL ,[fldEndTime] [datetime] NULL ,[fldStartTimeCollectedID] [int] NULL ,[fldEndTimeCollectedID] [int] NULL ,[fldStartArbStatus] [smallint] NULL ,[fldEndArbStatus] [smallint] NULL ,[fldDurationArbStatus] [smallint] NULL ,[fldPrimary] [smallint] NOT NULL ,[fldDateEntered] [datetime] NULL ,[fldEnteredBy] [int] NULL) ON [PRIMARY]GOALTER TABLE [dbo].[tblTSCollected] WITH NOCHECK ADDCONSTRAINT [DF_tblTSCollected_fldProcessed] DEFAULT (0) FOR[fldProcessed],CONSTRAINT [PK_tblTimesheetCollected] PRIMARY KEY CLUSTERED([fldCollectedID]) WITH FILLFACTOR = 90 ON [PRIMARY]GOALTER TABLE [dbo].[tblTSRuleApplied] WITH NOCHECK ADDCONSTRAINT [DF_tblTSRuleApplied_fldPrimary] DEFAULT (1) FOR[fldPrimary],CONSTRAINT [PK_tblTSRuleApplied] PRIMARY KEY CLUSTERED([fldRuleAppliedID]) WITH FILLFACTOR = 90 ON [PRIMARY] ,CONSTRAINT [IX_tblTSRuleApplied_1] UNIQUE NONCLUSTERED([fldStartTimeCollectedID],[fldEndTimeCollectedID]) WITH FILLFACTOR = 90 ON [PRIMARY]GOALTER TABLE [dbo].[tblTSCollected] ADDCONSTRAINT [FK_tblTSCollected_tblEmployee1] FOREIGN KEY([fldEmployeeID]) REFERENCES [dbo].[tblEmployee] ([fldEmployeeID]),CONSTRAINT [FK_tblTSCollected_tblLocation] FOREIGN KEY([fldLocationCode]) REFERENCES [dbo].[tblLocation] ([fldLocationCode]),CONSTRAINT [FK_tblTSCollected_tblTSRuleApplied] FOREIGN KEY([fldRuleAppliedID]) REFERENCES [dbo].[tblTSRuleApplied] ([fldRuleAppliedID])GOALTER TABLE [dbo].[tblTSRuleApplied] ADDCONSTRAINT [FK_tblTSRuleApplied_tblTSCollected] FOREIGN KEY([fldStartTimeCollectedID]) REFERENCES [dbo].[tblTSCollected] ([fldCollectedID]),CONSTRAINT [FK_tblTSRuleApplied_tblTSCollected1] FOREIGN KEY([fldEndTimeCollectedID]) REFERENCES [dbo].[tblTSCollected] ([fldCollectedID]),CONSTRAINT [FK_tblTSRuleApplied_tblTSDurationStatus] FOREIGN KEY([fldDurationArbStatus]) REFERENCES [dbo].[tblTSDurationStatus] ([fldStatus]),CONSTRAINT [FK_tblTSRuleApplied_tblTSEmpRules] FOREIGN KEY([fldEmpRuleID]) REFERENCES [dbo].[tblTSEmpRules] ([fldEmpRuleID]),CONSTRAINT [FK_tblTSRuleApplied_tblTSTimeStatus] FOREIGN KEY([fldStartArbStatus]) REFERENCES [dbo].[tblTSTimeStatus] ([fldStatus]),CONSTRAINT [FK_tblTSRuleApplied_tblTSTimeStatus1] FOREIGN KEY([fldEndArbStatus]) REFERENCES [dbo].[tblTSTimeStatus] ([fldStatus])GO
