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  • android SQLite vs Flat Files

    - by mixm
    hi. im creating a game right now and im a bit stuck on how to implement storage of levels. i need to be able to download level files from the internet ota. im not so familiar with transferring files ota, but i have some experience with databases (mysql). what would be a better way of storing the game's level data?

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  • C# Find out what column caused the Sql Exception

    - by PaN1C_Showt1Me
    Hi. I'm getting an exception from SQL Data Reader (MS SQL as datastore) and I'd like to know which column name causes this Exception to be thrown. But I cannot find it in the InnerException.. nowhere. ((System.InvalidOperationException)ex.InnerException).StackTrace: System.Data.SqlClient.SqlDataReader.ReadColumnHeader(Int32 i) System.Data.SqlClient.SqlDataReader.IsDBNull(Int32 i) ... Where is it hidden please ?

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  • Designing a table to store EXIF data

    - by rafale
    I'm looking to get the best performance out of querying a table containing EXIF data. The queries in question will only search the EXIF data for the specified strings and return the row index on a match. With that said, would it better to store the EXIF data in a table with separate columns for each of the tags, or would storing all of the tags in a single column as one long delimited string suit me just as well? There are around 115 EXIF tags I'll be storing, and each record would be around 1500 to 2000 chars in length if concatenated into a single string.

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  • Query two tables from different schema

    - by Guru
    Hi- I have two different schemas in Oracle (say S1, S2). And two tables in those schemas(say S1.Table1, S2.Table2). I want to query these two tables from schema S1. Both S1 and S2 are in different databases. From DB1 - Schema S1, I want to do something like this, select T1.Id from S1.Table1 T1 , S2.Table2 T2 Where T1.Id = T2.refId I know one way of doing this would be creating a DB Link for the second schema and use it in querying. But sadly, I don't have priv to create DB link. Is there some way to do without DB link, like, in TOAD, you can compare two schema objects. But again, two schema objects and it is general comparision. Not like querying them. Any ideas, suggestions are greatly appriciated. Thanks in advance.

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  • mysql and indexes with more than one column

    - by clarkk
    How to use indexes with more than one column The original index has an index on block_id, but is it necesarry when it's already in the unique index with two column? Indexes with more than one column (a,b,c) you can search for a, b and c you can search for a and b you can search for a you can not search for a and c Does this apply to unique indexes too? table id block_id account_id name indexes origin PRIMARY KEY (`id`) UNIQUE KEY `block_id` (`block_id`,`account_id`) KEY `block_id` (`block_id`), KEY `account_id` (`account_id`), indexes alternative PRIMARY KEY (`id`) UNIQUE KEY `block_id` (`block_id`,`account_id`) KEY `account_id` (`account_id`),

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  • Correct Sql Script for Formula

    - by Madan Madan
    Can anyone help me write SQL script for the following formula? If DEP = 1 If DROP 1 PLV = 334.86 * exp(0.3541 * ACTIVE_DAYS) + 0.25 * DROP + 20 * DEP Else If DROP < 0 PLV = DROP + 70 * ACTIVE_DAYS Else PLV = 0.25 * DROP + 70 * ACTIVE_DAYS The SQL script which I have is the following SELECT IF(dep=1, if(dep=1, (334.86 * exp(0.3541 * act_days)) + (0.25 * 'drop') + (20 * dep), if('drop'<0, 'drop' + (70 * act_days), (0.25 * 'drop') + (70 * act_days))),'0') as PLV But the above query is not right as something is missing where the formula says Else PLV = 0.26 * DROP Thanks,

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  • MySQL on Windows 7 multiple connections issue.

    - by Hussain
    I just installed MySql on windows 7 ... issue is i'm unable to get multiple connection to MySql . If I connect with command line than i'm unable to connect through any other client and vice versa. Previously I was using same version of MySql i.e. 5.1 on vista and it was working fine.

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  • Setting 0/1-to-1 relationship in SQLAlchemy?

    - by Timmy
    is there a proper way of setting up a 0/1-to-1 relationship? i want to be able to check if the related item exists without creating it: if item.relationship is None: item.relationship = item2() but it creates the insert statements on the if statement

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  • "SQLSTATE[23000]: Integrity constraint violation" in Doctrine

    - by rags
    Hi, i do get an Integrity constraint violation for Doctrine though i really can't see why. Schema.yml User: columns: id: type: integer primary: true autoincrement: true username: type: varchar(64) notnull: true email: type: varchar(128) notnull: true password: type: varchar(128) notnull: true relations: Websites: class: Website local: id foreign: owner type: many foreignType: one onDelete: CASCADE Website: columns: id: type: integer primary: true autoincrement: true active: type: bool owner: type: integer notnull: true plz: type: integer notnull: true longitude: type: double(10,6) notnull: true latitude: type: double(10,6) notnull: true relations: Owner: type: one foreignType: many class: User local: owner foreign: id And here's my data Fixtures (data.yml) Model_User: User_1: username: as email: as****.com password: ***** Model_Website: Website_1: active: true plz: 34222 latitude: 13.12 longitude: 3.56 Owner: User_1

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  • MySQL Throws NullReferenceException in Finalize... How are you coping with this?

    - by Cyril Gupta
    I am using MySQL with the .Net connector on 64 bit Windows. For some reason Mysql is throwing a NullReferenceException in Finalize. This is the problem here and it seems that its due to a bug described here. This bug was reported in 6.22, but I am getting the issue with 6.23 too so apparently it is not fixed. I am using MySQL both with the helper classes, and by instantiating the connection and the Mysqlcommand object. Does anybody have any idea what part of my code do I need to change to fix this issue? Cause even though this is a bug in Mysql this is not universal because I am not getting the problem in my other projects. MySQL bug report has no details on how to reproduce it either. Any suggestions?

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  • Prroblem with ObjectDelete() in Entity Framework 4

    - by Tom
    I got two entities: public class User : Entity { public virtual string Username { get; set; } public virtual string Email { get; set; } public virtual string PasswordHash { get; set; } public virtual List<Photo> Photos { get; set; } } and public class Photo : Entity { public virtual string FileName { get; set; } public virtual string Thumbnail { get; set; } public virtual string Description { get; set; } public virtual int UserId { get; set; } public virtual User User { get; set; } } When I try to delete the photo it works fine for the DB (record gets romoved from the table) but it doesnt for the Photos collection in the User entity (I can still see that photo in user.Photos). This is my code. What I'm doing wrong here? Changing entity properties works fine. When I change photo FileName for example it gets updated in DB and in user.Photos. var photo = SelectById(id); Context.DeleteObject(photo); Context.SaveChanges(); var user = GetUser(userName); // the photo I have just deleted is still in user.Photos also tried this but getting same results: var photo = user.Photos.First(); Context.DeleteObject(photo); Context.SaveChanges();

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  • Challege: merging csv files intelligently!

    - by Evenz495
    We are in the middle of changing web store platform and we need to import products' data from different sources. We currently have several different csv files from different it systems/databases because each system is missing some information. Fortunatly the product ids are the same so it's possible to relate the data using ids. We need to merge this data into one big csv file so we can import in into our new e-commerce site. My question: is there a general approach when you need to merge csv files with related data into one csv file? Are there any applications or tools that helps you out?

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  • Django: How/Where to store a value for a session without unnecessary DB hits

    - by GerardJP
    Hi all, I have an extended userprofile with AUTH_PROFILE_MODULE (ref: http://tinyurl.com/yhracqq) I would like to set a user.is_guru() method similar to user.is_active(). This would results for al views (or rather templates) to e.g. disable/enable certain user messages, displaying of widgets, etc. The boolean is stored in the extended user profile model, but I want to avoid hitting the DB for every view. So the questions is .. Do I use a context_processor, a template tag, session_dict or what have you to, possible cached, store this info for the duration of the users visit. Note: I dont have performance issues, so it's definitely filed under premature optimization. I just want to avoid generating extra work in the future :). Any pointers are very welcome. Thanx and greetz! Gerard.

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  • .NET Migrations Engine

    - by Karl Seguin
    I was once under the belief that Microsoft was working on an official, ruby-like, Migration framework. However, I haven't been able to find any additional information (or even the original source of my belief). Does anyone know any information about an official migration framework? or possibly an open source one?

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  • "select * into table" Will it work for inserting data into existing table

    - by Shantanu Gupta
    I am trying to insert data from one of my existing table into another existing table. Is it possible to insert data into any existing table using select * into query. I think it can be done using union but in that case i need to record all data of my existing table into temporary table, then drop that table and finally than apply union to insert all records into same table eg. select * into #tblExisting from tblExisting drop table tblExisting select * into tblExisting from #tblExisting union tblActualData Here tblExisting is the table where I actually want to store all data tblActualData is the table from where data is to be appended to tblExisting. Is it right method. Do we have some other alternative ?

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  • has anyone produced an in-memory GIT repository?

    - by Andrew Matthews
    I would like to be able to take advantage of the benefits of GIT (and its workflows), but without the cost of disk access - I just would like to leverage the distributed revision control capabilities of GIT to produce something like a hybrid of memcached and GIT. (preferably in .NET) Is there such a beast out there?

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  • How to do left joins with least-n-per-group query?

    - by Nate
    I'm trying to get a somewhat complicated query working and am not having any luck whatsoever. Suppose I have the following tables: cart_items: +--------------------------------------------+ | item_id | cart_id | movie_name | quantity | +--------------------------------------------+ | 0 | 0 | braveheart | 4 | | 1 | 0 | braveheart | 9 | | . | . | . | . | | . | . | . | . | | . | . | . | . | | . | . | . | . | +--------------------------------------------+ movies: +------------------------------+ | movie_id | movie_name | ... | +------------------------------+ | 0 | braveheart | . | | . | . | . | | . | . | . | | . | . | . | | . | . | . | +------------------------------+ pricing: +-----------------------------------------+ | id | movie_name | quantity | price_per | +-----------------------------------------+ | 0 | braveheart | 1 | 1.99 | | 1 | braveheart | 2 | 1.50 | | 2 | braveheart | 4 | 1.25 | | 3 | braveheart | 8 | 1.00 | | . | . | . | . | | . | . | . | . | | . | . | . | . | | . | . | . | . | | . | . | . | . | +-----------------------------------------+ I need to join the data from the tables, but with the added complexity that I need to get appropriate price_per from the pricing table. Only one price should be returned for each cart_item, and that should be the lowest price from the pricing table where the quantity for the cart item is at least the quantity in the pricing table. So, the query should return for each item in cart_items the following: +---------------------------------------------+ | item_id | movie_name | quantity | price_per | +---------------------------------------------+ Example 1: Variable passed to the query: cart_id = 0. Return: +---------------------------------------------+ | item_id | movie_name | quantity | price_per | +---------------------------------------------+ | 0 | braveheart | 4 | 1.25 | | 1 | braveheart | 9 | 1.00 | +---------------------------------------------+ Note that this is a minimalist example and that additional data will be pulled from the tables mentioned (particularly the movies table). How could this query be composed? I have tried using left joins and subqueries, but the difficult part is getting the price and nothing I have tried has worked. Thanks for your help. EDIT: I think this is similar to what I have working with my "real" tables: SELECT t1.item_id, t2.movie_name, t1.quantity FROM cart_items t1 LEFT JOIN movies t2 ON t2.movie_name = t1.movie_name WHERE t1.cart_id = 0 Assuming I wrote that correctly (I quickly tried to "port over" my real query), then the output would currently be: +---------------------------------+ | item_id | movie_name | quantity | +---------------------------------+ | 0 | braveheart | 4 | | 1 | braveheart | 9 | +---------------------------------+ The trouble I'm having is joining the price at a certain quantity for a movie. I simply cannot figure out how to do it.

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  • 2 Select or 1 Join query ?

    - by xRobot
    I have 2 tables: book ( id, title, age ) ---- 100 milions of rows author ( id, book_id, name, born ) ---- 10 millions of rows Now, supposing I have a generic id of a book. I need to print this page: Title: mybook authors: Tom, Graham, Luis, Clarke, George So... what is the best way to do this ? 1) Simple join like this: Select book.title, author.name From book, author WHERE ( author.book_id = book.id ) AND ( book.id = 342 ) 2) For avoid the join, I could make 2 simple query: Select title FROM book WHERE id = 342 Select name FROM author WHERE book_id = 342 What is the most efficient way ?

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  • Explain this SQL query in plain English.

    - by Kevinniceguy
    Please explain, in plain English, what question this SQL query answers: SELECT SUM(price) FROM Room r, Hotel h WHERE r.hotelNo = h.hotelNo and hotelName = 'Paris Hilton' and roomNo NOT IN (SELECT roomNo FROM Booking b, Hotel h WHERE (dateFrom <= CURRENT_DATE AND dateTo >= CURRENT_DATE) AND b.hotelNo = h.hotelNo AND hotelName = 'Paris Hilton');

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