An example of 4 rows on my table would be like this $1400 80 $1500 85 $1560 82 $1700 81
to calculate the average of the price sold related to the number of sold items just have to do Select avg(priceSold*itemsSold)
But sometimes i just want the average price of the first 100 sold items, so how can i make my query to just use the first 100 sold items?
in math it would be like this average= ( (1400*80) + (1500*20) ) / 100
but if i wanted the first 200 it would be like this average= ( (1400*80) + (1500*85) + (1560*35)) / 200
and if i wanted the first 300 would be like this average= ( (1400*80) + (1500*85) + (1560*82) + (1700*53)) / 300
but of course the number i want will always be a variable which is less than the total of the products sold. So, how the heck do i program this query where the number of the items sold is variable and it will take the rows of the database depending on how many items were sold.
I hope i didnt wrote my explanation too confusing and that i can get any help from you guys. thank you a lot for the help and byye
It seems to be subtracting the value of field3 from the total of 3 fields at some points instead of giving me the average.Some of the results are here:
Count Field1 Field2 Field3 Total Average ===== ====== ====== ====== ===== ======= 2NULL6NULL66 11NULL28134129 10NULL33NULL3333 3NULL12NULL1212
I want to calculate average row size of a record. By based on this i want to add some more columns into an existing table. Here is my table structureCREATE TABLE patient_procedure( proc_id int IDENTITY(1,1) CONSTRAINT proc_id_pri_key PRIMARY KEY, patient_id int NULL, surgeon_name varchar(40) NOT NULL, proc_name varchar(20) , part_name varchar(30), wth_contrast int , wthout_contrast int , wth_wthout_contrast int, xray_part varchar(60), arth_area varchar(30), others varchar(30) , cpt varchar(20) , procedure_date smalldatetime NOT NULL, mraloperrun varchar(20),CONSTRAINT patientid_foreign_key FOREIGN KEY(patient_id) REFERENCES dbo.patient_information (Patient_id)) Now i got a requirement that i have to add two more procedures with different columns.The columns overall size is 195 bytes.I can place those two procedures as seperate tables. I dont want to do that becuase of front end requirements.Here the problem is when the user enters these two procedures information remaining fields will store the null value. I know that when we store the null values into corresponding columns min of 1 byte will be occupied. Please suggest me that shall i include these columns into the above table. If i add these columns is performance will be decreased or not. Waiting for valuable suggestions.
Hi, How do I Calculate Average Leadtime... I have a Table named "iCalls_Calls" which has 2 Columns (start_Date and Closed_Date).I need to calculate average leadtime based on the columns from this table . I have a query and i need to add this ( calculate average leadtime) to this query.
Code:
SELECT B.USER_DIVISION,B.USER_DEPARTMENT,COUNT(*) FROM iCalls_Calls A INNER JOIN iCalls_Users B on A.REQUESTOR = B.USER_ID GROUP BY USER_DIVISION,USER_DEPARTMENT
Can anyone send me the correct query to calculate the average time ? Thanks..
I've got a statistics table that I've been writing to for about 2 years now. Every saturday night, a size (in MB) snapshot of each DB file is taken and dumped into this table. I'm then emailed a copy for that week.
Now, I'm trying to figure out what the fastest growers are. Here's the table ddl
What I'm trying to figure out is how to query the average monthly and yearly growth percentages per DB on the MDFSize column.
I'm usually pretty good at this sort of thing, but I just can't seem to wrap my head around how to solve this issue. I'm not having a very good math day.
What is the piece of SQL which looks at the average date difference for each enquiry and then sums it all up to give an overall average number of days it takes?
I need calculating a rolling 3 month average cost from the two dataset below. Which is the 3 month Average of Dataset1 / Dataset 2.
Dataset 1:
SELECT(factAdmissions.ContractCode + '-' +factAdmissions.BenefitPlanCode) AS [Contract Code], factAdmissions.AdmitCCYYMM, ISNULL(sum(AmountPaid),0)As [Amount Paid] FROM factAdmissions
[Code] ....
Dataset2:
Select
(factMembership.ContractCode+'-'+ factMembership.BenefitPlanCode) As Product, EffectiveCCYYMM, ISNULL(count(Distinct MemberId),0) As MemberCount From factMembership Where EffectiveCCYYMM >= '200701'
Hi All, we have collected perfmon data for a specific lun. Here is the background of the lun. The lun is Raid10 with 4 physical disks. We have problems interpreting the data. In the perfmon counter screen we have a max of 435 and average of 0.512. Can somebody tell us what is that we are missing? Any help is greatly appreciated.
i have problem regarding the row length and varchar. my problem is on every new row i have +6 more character on one of my field then the last record. and BOL says i can only have 8060 character per row. What i can not use the full lenght of varchar(8000) on field.
Hi, I am trying to insert text into a varchar(5000) column from a JAVA program. I am using MSDE database (which I believe is a strip down version of SQL7.0), with a variation of ms SQL Server 3.70.06.90 ODBC driver and tds jdbc driver from inet software. With the ODBC driver, I don't get any error but the data saved is only 255 characters. With the latter driver, I get a data truncation error and nothing is saved.
Hi,I have a pretty straightforward question to do with variable length fields I hope someone can help me with:When using varchar (or nvarchar), is there any point in specifying a smaller length than the maximum? Does it save space or improve performance at all?ThanksRedit: I suppose the max rowsize is an issue. any others?
a simple question to ask for varchar type. I want to update a varchar type parameter to a stored procedure to update a table. My question is , if I don't specify the length. and the varchar type will be trimmed to only 1 character. I thought it's supposed to be 50 by default? Besides if I need to compare varchar values, do I need to specify length as well? Cheers.
Hi, all I am seting up a table with email message, I am wondering what is the max length for varchar field. I am so reluctant to use text field, since when I run query for the descriptiona in sql analyzer, text field cannot be fully display in column. Any tricks to share? Thanks Betty
Hi, everyone, I want to know is there a way for me to set varchar to store more than 8000 characters? (I did checked from sql server books online and i know that the maximum storage for varchar, but i just want to know is there any exceptional way for me to store more than that).
I have a column set to varchar(12) so I can ensure that the length of the string entered will never be more than 12 characters but I want to limit the string to a minimum of 8 characters, so I end up with a string that is from 8-12 characters long. How do I ensure the minimum length of 8 characters? I'm using SQL Server 2005 if that helps. I tried adding a check constraint like so:
DATALENGTH(UserName) >= 8
But I keep getting an error when I save the table, so any help would be very much appreciated.
Hi all, I have a strange situation. I have a field in the database that has to be a string type field of around 4000 characters.
So naturally I setup the field as type: varchar length: 4000
However when I try to put any text in this field I find that I can put no more than 1023 characters of ascii text in there.
To check if this was a max record length prob I setup a test table with only 2 fields: ID: int, PK, Identity longVarchar: varchar, 4000
and tried to put some ascii text into the field called longVarchar. Again the most I could put in was 1023 characters!
Thinking that it could just be that SQL svr box that was wacky, I tried it on another one with the same result.
I have tried using other field types (nvarchar, char) and have found that they all could only hold 1023 characters max, no matter what how high I defined the size of the field.
Try it out yourselves and see if you get the same result. Any useful suggestions would really be appreciated.
Hi Everyone,I have a question about dynamically changing the length of a varchar(n)field, in case the value I'm trying to insert is too big and will givea "truncated" error, but before the error is given! i.e. Is there somekind of a way to "test" the length of the field while Inserting thevalue into it, and to have it automatically increase its length to thelength of the value being inserted, in case the value is too big?I've been able to do this in a "primitive" way, simply by identifyingthe specific error number in case the value is being truncated, andthen increasing the length of the varchar(n) field by using the ALTERcommand, and then duplicating the insert statement, but is there astandard (shorter) way of doing this?Here is my code (I'm working in an ASP environment):<%var_txt = "abcdefghijklmnopqrstuvwxyz12345678789"sql = "Insert Into Table1 (text) Values ('" & var_txt & "')"On Error Resume Nextconn.Execute sqlIf err = -2147217833 ThenResponse.Write "Error Recognized Successfully!<br /><br />"sql = "ALTER TABLE Table1 ALTER COLUMN text VARCHAR(" &Len(var_txt) &") NOT NULL"On Error Resume Nextconn.Execute sqlIf err<>0 ThenResponse.Write "Error while trying to alter Column:<br/>" & err & "= " & err.description & "<br />"ElseResponse.Write "Column altered successfully to: " &Len(var_txt) &"<br />"sql = "Insert Into Table1 (text) Values ('" & var_txt &"')"On Error Resume Nextconn.Execute sqlIf err<>0 ThenResponse.Write "<br />Error number 2:<br />" &err.description &"<br />"ElseResponse.Write "Now it was added successfully!HaHa!<br />"End IfEnd IfElseResponse.Write "Success."End If%>Thanks in advance!
I'm trying to get an understanding of a serious problem I have with a large DB in production. This is going to be obvious to someone (everyone probably) <bg>
I have a table which consists of numerous varchars and ints but also a Text type field. This table resides in a SQL 2000 Database. This DB currently has a data file size of 16Gb and a Transaction Log size of 17Gb. When I edit the table and increase the size of a Varchar field from 50 to 100 these files grow to more than double their size!
In my SQL Server Management Studio Express, I have a Database "testDb" that has a dbo.Inventory with a column "quantity". I executed the following sql script:
USE testDb
GO
CREATE FUNCTION AverageQuantity(@funcType varchar(20))
RETURNS numeric AS
BEGIN
DECLARE @average numeric
SELECT @average = AVG(quantity) FROM Inventory WHERE type=@funcType
RETURN @averge
END
GO
I got the following error message:
Msg 137, Level 15, State 2, Procedure AverageQuantity, Line 6
Must declare the scalar variable "@averge".
I think it was declared already in the BEGIN - END block. Please tell me why I got this error and advise me how to fix this problem.
I am currently working on a PHP based website that needs to be able to drawfrom Oracle, MS SQL Server, MySQL and given time and demand other RDBMS. Itook a lot of time and care creating a flexible and solid wrapper and amdeep into coding. The only problem is a noticed VARCHAR fields being drawnfrom SQL Server 2000 are being truncated to 255 characters.I searched around php.net and found the following :Note to Win32 Users: Due to a limitation in the underlying API used by PHP(MS DbLib C API), the length of VARCHAR fields is limited to 255. If youneed to store more data, use a TEXT field instead.(http://www.php.net/manual/en/functi...ield-length.php)The only problem with this advice is Text fields seem to be limited to 16characters in length, and I am having similar results in terms of truncationwith other character based fields that can store more than 255 characters.I am using PHP 4.3.3 running on IIS using the php_mssql.dll extensions andthe functions referenced here http://www.php.net/manual/en/ref.mssql.php.What are my options here? Has anybody worked around this or am I missingsomething obvious?James
we can use 'sp_executesql' to execute any statemens. I have made a search and people, seems, need the dynamic sql only to process some table/cloumn unknown in advance. My idea is that the dynamic SQL feature is ideal for passing blocks of code (aka delegates). Particularily, you may require to execute different procedures under some acquired locks. A procedure would acquire the locks, execute the code and release the locks. The problem is, however, that I cannot find the specification for the variable length parameters. It seems not feasible for SPs. Nevertheless, the 'sp_executesql itself does accept the variable number of parameters. How? Can we look at the defenition?
I'm new to SQL Server. I installed a copy of 6.5 on my server and set it up today. I received a db from a colleague and have been unable to find out what the variable types and lengths are. This may be very easy but I need to know.
