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  • Advice on simple efficient way to store web form data when no db/auth required

    - by ted776
    Hi, I have a situation where I need to provide an efficient way to process and store comments submitted via a web form. I would normally use PHP and either MySQL or XML to store the data, but this is slightly different in that this web form will only be temporarily available in a closed LAN environment, and all i need to do is process the form data and store it a format which can be accessed by another application on the LAN (Adobe Director). Each request made by the Director app should pop the stack of data. I'm wondering how best to store the data for this type of situation as it's not something I would normally do. I'm thinking possibly storing the data in an XML file, but any advice would be great!

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  • MS Query Analizer/Management Studio replacement?

    - by kprobst
    I've been using SQL Server since version 6.5 and I've always been a bit amazed at the fact that the tools seem to be targeted to DBAs rather than developers. I liked the simplicity and speed of the Query Analizer for example, but hated the built-in editor, which was really no better than a syntax coloring-capable Notepad. Now that we have Management Studio the management part seems a bit better but from a developer standpoint the tools is even worse. Visual Studio's excellent text editor... without a way to customize keyboard bindings!? Don't get me started on how unusable is the tree-based management hierarchy. Why can't I re-root the tree on a list of stored procs for example the way the Enterprise Manager used to allow? Now I have a treeview that needs to be scrolled horizontally, which makes it eminently useless. The SQL server support in Visual Studio is fantastic for working with stored procedures and functions, but it's terrible as a general ad hoc data query tool. I've tried various tools over the years but invariably they seem to focus on the management side and shortchange the developer in me. I just want something with basic admin capabilities, good keyboard support and requisite DDL functionality (ideally something like the Query Analyzer). At this point I'm seriously thinking of using vim+sqlcmd and a console... I'm that desperate :) Those of you who work day in and day out with SQL Server and Visual Studio... do you find the tools to be adequate? Have you ever wished they were better and if you have found something better, could you share please? Thanks!

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  • make multiple, composite query in oracle

    - by Meloun
    How can i make multiple, composite query in oracle? for example this several queries in one step? 1 CREATE TABLE test (id NUMBER PRIMARY KEY, name VARCHAR2(30)); 2 CREATE SEQUENCE test_sequence START WITH 1 INCREMENT BY 1; 3 CREATE OR REPLACE TRIGGER test_trigger BEFORE INSERT ON test REFERENCING NEW AS NEW FOR EACH ROW BEGIN SELECT test_sequence.nextval INTO :NEW.ID FROM dual; END; 4 INSERT INTO test (name) VALUES ('Jon'); 5 INSERT INTO test (name) VALUES ('Meloun');

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  • Retrieving all objects in code upfront for performance reasons

    - by ming yeow
    How do you folks retrieve all objects in code upfront? I figure you can increase performance if you bundle all the model calls together? This makes for a bigger deal, especially if your DB cannot keep everything in memory def hitDBSeperately { get X users ...code get Y users... code get Z users... code } Versus: def hitDBInSingleCall { get X+Y+Z users code for X code for Y... }

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  • How can I save the schema of a SQL Database to a file?

    - by Eric
    I'm writing a software application in C#.Net that connects to a SQL Server database. My C# project is under SVN version control, but I'd like to include my database schema in the SVN repository as well. An answer to a previous question of mine suggested storing the scripts to generate the database in version control. Is there a way to automatically generate these scripts from an existing database? I'm very new to SQL Server, but I noticed in management studio that the SQL commands to create a table can be generated automatically by right clicking on the table and clicking "Script Table As". Is there an equivalent command that would work with the entire database?

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  • How to achieve high availability?

    - by tanyehzheng
    My boss wants to have a system that takes into concern of continent wide catastrophic event. He wants to have two servers in US and two servers in Asia (1 login server and 1 worker server in each continent). In the event that earthquake breaks the connection between the two continents, both should work alone. When the connection is revived, they should sync each other back to normal. External cloud system not allowed as he has no confidence. The system should take into account of scalability which means addition of new servers should be easy to configure. The servers should be load balanced. The connection between the servers should be very secure(encrypted and send through SSL although SSL takes care of encryption). The system should let one and only one user log in with one account. (beware of latency between continent and two users sharing account may reach both login server at the same time) Please help. I'm already at the end of my wit. Thank you in advance.

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  • Using Entity Framework, how do I specify a sort on a navagation property?

    - by Jared
    I have two tables: [Category], [Item]. They are connected by a join table: [CategoryAndItem]. It has two primary key fields: [CategoryKey], [ItemKey]. Foreign keys exist appropriately and Entity has no problem pulling this in and creating the correct navigation properties that connect the entity objects. Basically each category can have multiple items, and items can be in multiple categories. The problem is that the order of items is specified per category, so that a particular item might be third in one category but fifth in another. In the past, I have added a [Sequence] field to the join table and modified the stored procedure to handle it. But since Entity is replacing my stored procedures, I need to figure out how to make Entity handle the sequence. Any suggestions?

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  • Which Oracle table uses a sequence?

    - by Jaú
    Having a sequence, I need to find out which table.column gets its values. As far as I know, Oracle doesn't keep track of this relationship. So, looking up for the sequence in source code would be the only way. Is that right? Anyone knows of some way to find out this sequence-table relationship?

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  • SQLAlchemy - relationship limited on more than just the foreign key

    - by Marian
    I have a wiki db layout with Page and Revisions. Each Revision has a page_id referencing the Page, a page relationship to the referenced page; each Page has a all_revisions relationship to all its revisions. So far so common. But I want to implement different epochs for the pages: If a page was deleted and is recreated, the new revisions have a new epoch. To help find the correct revisions, each page has a current_epoch field. Now I want to provide a revisions relation on the page that only contains its revisions, but only those where the epochs match. This is what I've tried: revisions = relationship('Revision', primaryjoin = and_( 'Page.id == Revision.page_id', 'Page.current_epoch == Revision.epoch', ), foreign_keys=['Page.id', 'Page.current_epoch'] ) Full code (you may run that as it is) However this always raises ArgumentError: Could not determine relationship direction for primaryjoin condition ...`, I've tried all I had come to mind, it didn't work. What am I doing wrong? Is this a bad approach for doing this, how could it be done other than with a relationship?

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  • Systems design question: DB connection management in load-balanced n-tier

    - by aoven
    I'm wondering about the best approach to designing a DB connection manager for a load-balanced n-tier system. Classic n-tier looks like this: Client -> BusinessServer -> DBServer A load-balancing solution as I see it would then look like this: +--> ... +--+ +--> BusinessServer +--+--> SessionServer --+ Client -> Gateway --+--> BusinessServer +--| +--> DBServer +--> BusinessServer +--+--------------------+ +--> ... +--+ As pictured, the business server component is being load-balanced via multiple instances, and a hardware gateway is distributing the load among them. Session server probably needs to be situated outside the load-balancing array, because it manages state, which mustn't be duplicated. Barring any major errors in design so far, what is the best way to implement DB connection management? I've come up with a couple of options, but there may be others I'm not aware of: Introduce a new Broker component between the DBServer and the other components and let it handle the DB connections. The upside is that all the connections can be managed from a single point, which is very convenient. The downside is that now there is an additional "single point of failure" in the system. Other components must go through it for every request that involves DB in some way, which also makes this a bottleneck. Move the DB connection management into BusinessServer and SessionServer components and let each handle its own DB connections. The upside is that there is no additional "single point of failure" or bottleneck components. The downside is that there is also no control over possible conflicts and deadlocks apart from what DBServer itself can provide. What else can be done? FWIW: Technology is .NET, but none of the vendor-specific stacks are used (e.g. no WCF, MSMQ or the like).

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  • What is a good DBMS for archiving?

    - by Thomas.Winsnes
    I've been stuck in a MsSql/MySql world now for a few years, and I've decided to spread my wings a little further. At the moment I'm researching which DBMS is good at things needed when archiving data. Eg. lots of writes and low reads. I've seen the NoSQL crusade, but I have a very RDBMS mindset, so I'm a bit skeptical. Anyone have any suggestions? Or even any pointers to where there are some benchmarks etc for this kind of stuff. Thank you :) Thomas

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  • How can I view live MySQL queries?

    - by barfoon
    Hey all, I am just wondering if its possible to trace MySQL queries on my linux server as they happen? For example I'd love to set up some sort of listener, then request a web page and view all of the queries the engine executed, or just view all of the queries being run on a production server. Are there tools to do this? Thank you,

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  • BI with Django?

    - by Helmut
    Is there a way to develop Bi (Business Intelligence) solutions with Django? Therefore it should be possible to define models with more than one Datasource. Is anybody out there who has experienced BI with Django? How could it work ?

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  • Question About DateCreated and DateModified Columns - SQL Server

    - by user311509
    CREATE TABLE Customer ( customerID int identity (500,20) CONSTRAINT . . dateCreated datetime DEFAULT GetDate() NOT NULL, dateModified datetime DEFAULT GetDate() NOT NULL ); When i insert a record, dateCreated and dateModified gets set to default date/time. When i update/modify the record, dateModified and dateCreated remains as is? What should i do? Obviously, i need to dateCreated value to remain as was inserted the first time and dateModified keeps changing when a change/modification occurs in the record fields. In other words, can you please write a sample quick trigger? I don't know much yet...

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  • MongoDB RSS Feed Entries, Embed the Entries in the Feed Object?

    - by Patrick Klingemann
    I am saving a reference to an RSS Feed in MongoDB, each Feed has an ever growing list of Entries. As I'm designing my schema, I'm concerned about this statement from the MongoDB Schema Design - Embed vs. Reference Documentation: If the amount of data to embed is huge (many megabytes), you may read the limit on size of a single object. This will surely happen if I understand the statement correctly. So the question is, I am correct to assume that I should not embed the Feed Entries within a Feed because I'll eventually reach the limit on size of a single object?

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  • How to track history of db tables that include many-to-many mapping tables?

    - by chacmool
    I have seen several questions here on tracking db history, but can't seem to find one that matches our situation. We need to track the history of several tables, some of which are many-to-many linking tables. Eg say we have this schema: EntityA id name EntityB id name ABLink A_id B_id So, tracking changes to EntityA or EntityB seems pretty straightforward. We can keep a log table with the same columns plus a date stamp and user. But what about the links? How do we maintain the set of links that are valid for a given version of the data? We need to be able to recreate a history of the data showing changes in chronological order. So if a link added or deleted, we indicate that. Etc.

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  • Hierarchical Data in MySQL is as fast as XML to retrieve?

    - by ajsie
    i've got a list of all countries - states - cities (- subcities/villages etc) in a XML file and to retrieve for example a state's all cities it's really quick with XML (using xml parser). i wonder, if i put all this information in mysql, is retrieving a state's all cities as fast as with XML? cause XML is designed to store hierarchical data while relational databases like mysql are not. the list contains like 500 000 entities. so i wonder if its as fast as XML using either of: Adjacency list model Nested Set model And which one should i use? Cause (theoretically) there could be unlimited levels under a state (i heard that adjacency isn't good for unlimited child-levels). And which is fastest for this huge dataset? Thanks!

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  • Ruby on Rails Mongrel web server stuck when MySQL service is running

    - by Marcos Buarque
    Hi, I am a Ruby on Rails newbie and already have a problem. I have started the Mongrel web server and it works fine when MySQL service isn't running. But when MySQL is on, Mongrel stucks. It ceases from serving the pages. So far, I have tested the localhost:3000 URL. When MySQL is off, it serves the page. When I click "about application's environment", I get the messasge (of course) "Can't connect to MySQL server on 'localhost' (10061)". After starting the MySQL service and refreshing, I get no more answer and Mongrel does not serve the webpage. It gets stuck with no answer to the browser. Then I have to stop the webserver and restart it. I have installed mysql2 gem with the command gem install mysql2. I was able to create the _test and _development databases with the command line rake db:create. I have tested with MySQL root user and blank password and also tried with a superuser user I have created. No success. Here is the server log: ======================== Started GET "/rails/info/properties" for 127.0.0.1 at Fri Dec 24 17:41:25 -0200 2010 Mysql2::Error (Can't connect to MySQL server on 'localhost' (10061)): Rendered C:/Ruby187/lib/ruby/gems/1.8/gems/actionpack-3.0.3/lib/action_dispatch/middleware/templates/rescues/_trace.erb (1.0ms) Rendered C:/Ruby187/lib/ruby/gems/1.8/gems/actionpack-3.0.3/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb (5.0ms) Rendered C:/Ruby187/lib/ruby/gems/1.8/gems/actionpack-3.0.3/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb within rescues/layout (35.0ms) ================= I am running on a Windows 7 environment with firewall down.

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  • Does Ruby on Rails "has_many" array provide data on a "need to know" basis?

    - by Jian Lin
    On Ruby on Rails, say, if the Actor model object is Tom Hanks, and the "has_many" fans is 20,000 Fan objects, then actor.fans gives an Array with 20,000 elements. Probably, the elements are not pre-populated with values? Otherwise, getting each Actor object from the DB can be extremely time consuming. So it is on a "need to know" basis? So does it pull data when I access actor.fans[500], and pull data when I access actor.fans[0]? If it jumps from each record to record, then it won't be able to optimize performance by doing sequential read, which can be faster on the hard disk because those records could be in the nearby sector / platter layer -- for example, if the program touches 2 random elements, then it will be faster just to read those 2 records, but what if it touches all elements in random order, then it may be faster just to read all records in a sequential way, and then process the random elements. But how will RoR know whether I am doing only a few random elements or all elements in random?

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  • How to efficiently store and update binary data in Mongodb?

    - by Rocketman
    I am storing a large binary array within a document. I wish to continually add bytes to this array and sometimes change the value of existing bytes. I was looking for some $append_bytes and $replace_bytes type of modifiers but it appears that the best I can do is $push for arrays. It seems like this would be doable by performing seek-write type operations if I had access somehow to the underlying bson on disk, but it does not appear to me that there is anyway to do this in mongodb (and probably for good reason). If I were instead to just query this binary array, edit or add to it, and then update the document by rewriting the entire field, how costly will this be? Each binary array will be on the order of 1-2MB, and updates occur once every 5 minutes and across 1000s of documents. Worse, yet there is no easy way to spread these out (in time) and they will usually be happening close to one another on the 5 minute intervals. Does anyone have a good feel for how disastrous this will be? Seems like it would be problematic. An alternative would be to store this binary data as separate files on disk, implement a thread pool to efficiently manipulate the files on disk, and reference the filename from my mongodb document. (I'm using python and pymongo so I was looking at pytables). I'd prefer to avoid this though if possible. Is there any other alternative that I am overlooking here? Thanks in advnace.

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