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  • SQL with codition on calculated value

    - by user619893
    I have a table with products, their amount and their price. I need to select all entries where the average price per article is between a range. My query so far: SELECT productid,AVG(SUM(price)/SUM(amount)) AS avg FROM stock WHERE avg=$from AND avg<=$to GROUP BY productid If do this, it tells me avg doesnt exist. Also i obviously need to group by because the sum and average need to be per wine

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  • sports league database design

    - by John
    Hello, I'm developing a database to store statistics for a sports league. I'd like to show several tables: - league table that indicates the position of the team in the current and previous fixture - table that shows the position of a team in every fixture in the championship I have a matches table: Matches (IdMatch, IdTeam1, IdTeam2, GoalsTeam1, GoalsTeam2) Whith this table I can calculate the total points of every team based on the matches the team played. But every time I want to show the league table I have to calculate the points. Also I have a problem to calculate in which position classified a team in the last 10 fixtures cause I have to make 10 queries. To store the league table for every fixture in a database table is another approach, but every time I change a match already played I have to recalculate every fixture from there... Is there a better approach for this problem? Thanks

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  • Multiple column Union Query without duplicates

    - by Adam Halegua
    I'm trying to write a Union Query with multiple columns from two different talbes (duh), but for some reason the second column of the second Select statement isn't showing up in the output. I don't know if that painted the picture properly but here is my code: Select empno, job From EMP Where job = 'MANAGER' Union Select empno, empstate From EMPADDRESS Where empstate = 'NY' Order By empno The output looks like: EMPNO JOB 4600 NY 5300 MANAGER 5300 NY 7566 MANAGER 7698 MANAGER 7782 MANAGER 7782 NY 7934 NY 9873 NY Instead of 5300 and 7782 appearing twice, I thought empstate would appear next to job in the output. For all other empno's I thought the values in the fields would be (null). Am I not understanding Unions correctly, or is this how they are supposed to work? Thanks for any help in advance.

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  • Database table schema design - varchar(n). Suitable choice of N

    - by morpheous
    Coming from a C background, I may be getting too anal about this and worrying unnecessarily about bits and bytes here. Still, I cant help thinking how the data is actually stored and that if I choose an N which is easily factorizable into a power of 2, the database will be more effecient in how it packs data etc. Using this "logic", I have a string field in a table which is a variable length up to 21 chars. I am tempted to use 32 instead of 21, for the reason given above - however now I am thinking that I am wasting disk space because there will be space allocated for 11 extra chars that are guaranteed to be never used. Since I envisage storing several tens of thousands of rows a day, it all adds up. Question: Mindful of all of the above, Should I declare varchar(21) or varchar(32) and why?

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  • MySQL - Limit a left join to the first date-time that occurs?

    - by John M
    Simplified table structure (the tables can't be merged at this time): TableA: dts_received (datetime) dts_completed (datetime) task_a (varchar) TableB: dts_started (datetime) task_b (varchar) What I would like to do is determine how long a task took to complete. The join parameter would be something like ON task_a = task_b AND dts_completed < dts_started The issue is that there may be multiple date-times that occur after the dts_completed. How do I create a join that only returns the first tableB-datetime that occurs after the tableA-datetime?

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  • Join with table and sub query in oracle

    - by Amandeep
    I dont understand what is wrong with this query it is giving me compile time error of command not ended properly.The inner query is giving me 4 records can any body help me out. select WGN3EVENTPARTICIPANT.EVENTUID from (Select WGN_V_ADDRESS_1.ADDRESSUID1 as add1, WGN_V_ADDRESS_1.ADDRESSUID2 as add2 from WGN3USER inner join WGN_V_ADDRESS_1 on WGN_V_ADDRESS_1.USERID=wgn3user.USERID where WGN3USER.USERNAME='FIRMWIDE\khuraj' ) as ta ,WGN3EVENTPARTICIPANT where (ta.ADDRESSUID1=WGN3EVENTPARTICIPANT.ADDRESSUID1) AND (ta.ADDRESSUID2=WGN3EVENTPARTICIPANT.ADDRESSUID2) I am running it in oracle. Thanks Amandeep

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  • Database design 1 to 1 relationship

    - by Khou
    I design my database incorrectly, should I fix this while its in development? "user" table is suppose to have a 1.1 relationship with "userprofile" table however the actual design the "user" table has a 1.* relationship with "userprofile" table. Everything works! but should it be fixed anyways?

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  • Oracle - truncating a global temporary table

    - by superdario
    I am processing large amounts of data in iterations, each and iteration processes around 10-50 000 records. Because of such large number of records, I am inserting them into a global temporary table first, and then process it. Usually, each iteration takes 5-10 seconds. Would it be wise to truncate the global temporary table after each iteration so that each iteration can start off with an empty table? There are around 5000 iterations.

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  • Have 2 separate tables or an additional field in 1 table?

    - by hkansal
    Hello, I am making a small personal application regarding my trade of shares of various companies. The actions can be selling shares of a company or buying. Therefore, the details to be saved in both cases would be: Number of Shares Average Price Would it be better to use a separate tables for "buy" and "sell" or just use one table for "trade" and keep a field that demarcates "buy" from "sell"?

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  • joining two tables and getting aggregate data

    - by alex
    how do i write a query that returns aggregate sales data for California in the past x months. ----------------------- ----------------------- | order | | customer | |-----------------------| |-----------------------| | orderId int | | customerId int | | customerId int | | state varchar | | deposit decimal | ----------------------- | orderDate date | ----------------------- ----------------------- | orderItem | |-----------------------| | orderId int | | itemId int | | qty int | | lineTotal decimal | | itemPrice decimal | -----------------------

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  • How do I get the earlist DateTime of a set, where there is a few conditions

    - by radbyx
    Create script for Product SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO SET ANSI_PADDING ON GO CREATE TABLE [dbo].[Product]( [ProductID] [int] IDENTITY(1,1) NOT NULL, [ProductName] [varchar](50) NOT NULL, CONSTRAINT [PK_Products] PRIMARY KEY CLUSTERED ( [ProductID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO SET ANSI_PADDING OFF GO Create script for StateLog SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[StateLog]( [StateLogID] [int] IDENTITY(1,1) NOT NULL, [ProductID] [int] NOT NULL, [Status] [bit] NOT NULL, [TimeStamp] [datetime] NOT NULL, CONSTRAINT [PK_Uptime] PRIMARY KEY CLUSTERED ( [StateLogID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[StateLog] WITH CHECK ADD CONSTRAINT [FK_Uptime_Products] FOREIGN KEY([ProductID]) REFERENCES [dbo].[Product] ([ProductID]) GO ALTER TABLE [dbo].[StateLog] CHECK CONSTRAINT [FK_Uptime_Products] GO I have this and it's not enough: select top 5 [ProductName], [TimeStamp] from [Product] inner join StateLog on [Product].ProductID = [StateLog].ProductID where [Status] = 0 order by TimeStamp desc; (My query givess the 5 lastest TimeStamp's where Status is 0(false).) But I need a thing more: Where there is a set of lastest TimeStamps for a product where Status is 0, i only want the earlist of them (not the lastet). Example: Let's say for Product X i have: TimeStamp1(status = 0) TimeStamp2(status = 1) TimeStamp3(status = 0) TimeStamp4(status = 0) TimeStamp5(status = 1) TimeStamp6(status = 0) TimeStamp7(status = 0) TimeStamp8(status = 0) Correct answer would then be:: TimeStamp6, because it's the first of the lastest timestamps.

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  • Centralizing / Abstracting MSSQL Data from Multiple Tables / Databases

    - by davemackey
    If one has a number of databases (due to separate application front-ends) that provide a complete picture - for example a CRM, accounting, and product database - what methods are available to centralize/abstract this data for easy reporting? Essentially, I'm wondering if there is a way to automatically pull data from multiple databases into a central repository that is continuously updated from the three databases and which can be used for reporting? I'm also open to alternative best practice suggestions?

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  • MySQL Delete Records Older Than X Minutes?

    - by sajanNOPPIX
    I've searched quite a bit and found a few solutions that didn't end up working for me and can't understand why. I have a table with a timestamp column. The MySQL type for this column is 'datetime'. I insert into this table the following from PHP. date('Y-m-d H:i:s') This enters, what looks like the correct value for the MySQL date time. 2012-06-28 15:31:46 I want to use this column to delete rows that are older than say 10 minutes. I'm running the following query, but it's not working. It affects 0 rows. DELETE FROM adminLoginLog WHERE timestamp < (NOW() - INTERVAL 10 MINUTE); Can anyone shed some light as to what I'm doing wrong and why it's not working properly? Thanks. Update: It looks like my first issue is that I'm using DATETIME when I should be using the TIMESTAMP data type. I'm updating my code to do that now. Thanks.

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  • How can I find days between different paired rows?

    - by Anthony
    I've been racking my brain about how to do this in one query without PHP code. In a nutshell, I have a table that records email activity. For the sake of this example, here is the data: recipient_id activity date 1 delivered 2011-08-30 1 open 2011-08-31 2 delivered 2011-08-30 3 delivered 2011-08-24 3 open 2011-08-30 3 open 2011-08-31 The goal: I want to display to users a single number that tells how many recipients open their email within 24 hours. E.G. "Users that open their email within 24 hours: 13 Readers" In the case of the sample data, above, the value would be "1". (Recipient one was delivered an email and opened it the next day. Recipient 2 never opened it and recipient 3 waited 5 days.) Can anyone think of a way to express the goal in a single query? Reminder: In order to count, the person must have a 'delivered' tag and at least one 'open' tag. Each 'open' tag only counts once per recipient.

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  • Merging some columns of two mysql tables where id = fileid

    - by garg
    There are two tables TableA filedata_id | user_id | filename 1 | 1 | file.txt 2 | 1 | file2.txt TableB a_id | date | filedataid | counter | state | cat_id | subcat_id | med_id 99 | 1242144 | 1 | 2 | v | 55 | 56 | 90 100 | 1231232 | 2 | 3 | i | 44 | 55 | 110 I want to move columns cat_id, subcat_id, med_id to TableA where tableA.filedata_id = TableB.filedataid The result should be: TableA filedata_id | user_id | filename | cat_id | subcat_id | med_id 1 | 1 | file.txt | 55 | 56 | 90 2 | 1 | file2.txt | 44 | 55 | 110 and so on. Is there a way to do this easily?

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  • how to select distinct rows for a column

    - by Satoru.Logic
    Hi, all. I have a table x that's like the one bellow: id | name | observed_value | 1 | a | 100 | 2 | b | 200 | 3 | b | 300 | 4 | a | 150 | 5 | c | 300 | I want to make a query so that in the result set I have exactly one record for one name: (1, a, 100) (2, b, 200) (5, c, 300) If there are multiple records corresponding to a name, say 'a' in the table above, I just pick up one of them. In my current implementation, I make a query like this: select x.* from x , (select distinct name, min(observed_value) as minimum_val from x group by name) x1 where x.name = x1.name and x.observed_value = x1.observed_value; But I think there may be some better way around, please tell me if you know, thanks in advance.

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