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  • trying to use ActiveRecord with Sinatra, Migration fails question

    - by David Lazar
    Hi, running Sinatra 1.0, I wanted to add a database table to my program. In my Rakefile I have a task task :environment do ActiveRecord::Base.establish_connection(YAML::load(File.open('config/database.yml'))["development"]) end I have a migration task in my namespace that calls the migration code: namespace :related_products do desc "run any migrations we may have in db/migrate" task :migrate => :environment do ActiveRecord::Migrator.migrate('db/migrate', ENV["VERSION"] ? ENV["VERSION"].to_i : nil ) end My console pukes out an error when the call to ActiveRecord::MIgrator.migrate() is made. rake aborted! undefined method `info' for nil:NilClass The migration code itself is pretty simple... and presents me with no clues as to what this missing info class is. class CreateStores < ActiveRecord::Migration def self.up create_table :stores do |t| t.string :name t.string :access_url t.timestamps end end def self.down drop_table :stores end end I am a little mystified here and am looking for some clues as to what might be wrong. Thanks!

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  • How sophisticated should be DAL?

    - by Andrew Florko
    Basically, DAL (Data Access Layer) should provide simple CRUD (Create/Read/Update/Delete) methods but I always have a temptation to create more sophisticated methods in order to minimize database access roundtrips from Business Logic Layer. What do you think about following extensions to CRUD (most of them are OK I suppose): Read: GetById, GetByName, GetPaged, GetByFilter... e.t.c. methods Create: GetOrCreate methods (model entity is returned from DB or created if not found and returned), Create(lots-of-relations) instead of Create and multiple AssignTo methods calls Update: Merge methods (entities list are updated, created and deleted in one call) Delete: Delete(bool children) - optional children delete, Cleanup methods Where do you usually implement Entity Cache capabilities? DAL or BLL? (My choice is BLL, but I have seen DAL implementations also) Where is the boundary when you decide: this operation is too specific so I should implement it in Business Logic Layer as DAL multiple calls? I often found insufficient BLL operations that were implemented in dozen database roundtrips because developer was afraid to create a bit more sophisticated DAL. Thank you in advance!

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  • .net converting bytearray to double[]

    - by AJ
    Hello, I am working with a database from a legacy app which stores 24 floating point values (doubles) as a byte array of length 192, so 8 bytes per value. This byte array is stored in a column of type image in a SQL Server 2005 database. In my .net app I need to read this byte array and convert it to a array of type Double[24]. I can access the field easy enough reader.GetBytes(...) but how to convert the returned ByteArray to Double[24] Any ideas? Thanks, AJ

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  • SQLAlchemy - how to map against a read-only (or calculated) property

    - by Jeff Peck
    I'm trying to figure out how to map against a simple read-only property and have that property fire when I save to the database. A contrived example should make this more clear. First, a simple table: meta = MetaData() foo_table = Table('foo', meta, Column('id', String(3), primary_key=True), Column('description', String(64), nullable=False), Column('calculated_value', Integer, nullable=False), ) What I want to do is set up a class with a read-only property that will insert into the calculated_value column for me when I call session.commit()... import datetime def Foo(object): def __init__(self, id, description): self.id = id self.description = description @property def calculated_value(self): self._calculated_value = datetime.datetime.now().second + 10 return self._calculated_value According to the sqlalchemy docs, I think I am supposed to map this like so: mapper(Foo, foo_table, properties = { 'calculated_value' : synonym('_calculated_value', map_column=True) }) The problem with this is that _calculated_value is None until you access the calculated_value property. It appears that SQLAlchemy is not calling the property on insertion into the database, so I'm getting a None value instead. What is the correct way to map this so that the result of the "calculated_value" property is inserted into the foo table's "calculated_value" column?

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  • where should I put the EF entity and data annotations in asp.net mvc + entity framework project

    - by giddy
    So I have a DataEntity class generated by EntityFramework4 for my sqlexpress08 database. This data context is exposed via a WCF Data Service/Odata to silverlight and win forms clients. Should the data entities + edmx file (generated by EF4) go in a separate class library? The problem here then is I would specify data annotations for a few entities and then some of them would require specific MVC attributes (like CompareAttribute) so the class library would also reference mvc dlls. There also happen to be entity users which will be encapsulated or wrapped into an IIdentity in the website. So its pretty tied to the mvc website. Or Should it maybe go in a Base folder in the mvc project itself? Mostly the website is data driven around the database, like approve users, change global settings etc. The real business happens in the silverlight and win forms apps. Im using mvc3 rc2 with Razor. Thanks

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  • Mixing Transaction Script pattern with DDD/CQRS

    - by Herman
    Hi all, Here is the situation, in order to support our legacy system, we need to insert to a table whenever a user logs in. This is basically an CRUD operation, so it doesn't really make sense to create repository/entity/command/event for this since this doesn't tie to any business rules at all. The only benefit to create a CQRS command is that this database write can happen asynchronously under that model. Which is a better route to take? Use CQRS, and then call a stored proc. when handling that command? Just call database directly in the controller (I am using asp.net mvc)

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  • ZendFramework integration with other frameworks

    - by St.Woland
    I want to make this question a guide for those interested in ZendFramework integration with other libraries/frameworks. Searching over StackOverflow doesn't give a broad view on the subject. The question is: which libraries/frameworks do you use in your current ZF-based project? what are the best practices for ZF-based project architecture? I don't mean any components that are already a part of ZF. Please give a description of aditional frameworks you have integrated (like RuckUsing, Smarty, or Doctrine). It also applies to any GUI frameworks (perhaps you use a CSS framework), as well as JS frameworks (not just jQuery or prototype, but rather some advanced structures). The main requirement: it has to be a ZendFramework project. Additional bonus will be given to answers that describe performance optimization.

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  • Entity Framework doesn't like 0..1 to * relationships.

    - by Orion Adrian
    I have a database framework where I have two tables. The first table has a single column that is an identity and primary key. The second table contains two columns. One is a nvarchar primary key and the other is a nullable foreign key to the first table. On the default import of the database I get the following error: Condition cannot be specified for Column member 'ForeignKeyId' because it is marked with a 'Computed' or 'Identity' StoreGeneratedPattern. where ForeignKeyId is the second foreign key reference in the second table. Is this just something the entity model doesn't do? Or am I missing something?

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  • Most elegant way to morph this sequence

    - by Ed Woodcock
    Hi folks: I've got the Day of the week stored in a database table (that I do not control), and I need to use it in my code. Problem is, I want to use the System.DayOfWeek enum for representation for this, and the sequences are not the same. In the database, it's as follows: 1 2 3 4 5 6 7 S M T W T F S I need it as follows: 0 1 2 3 4 5 6 M T W T F S S What's the most elegant way to do this? for example, I could do: i = dayOfWeek; i = i - 2; if (i < 0) { i = 6; } but that's a bit inelegant. Any suggestions?

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  • What is the best PHP framework for building a website around a heavily relational PostgreSQL databas

    - by Kenaniah
    First of all, the framework of choice needs to have excellent support for PostgreSQL. I don't care about MySQL because it doesn't have half of the features the application I will be porting requires. (And when I say excellent support, I mean that their approach to database drivers has not been solely trained in MySQL). The ideal framework: Should take full advantage of PHP 5.3 and PostgreSQL 8.4 features Should support new technologies such as OpenID and social networking Should support complex relationships between database relations Should have an intelligent validation system Should have a basic library of helpful views (such as pagination, navigation, etc) Should probably be MVC based Should have excellent documentation and an active development community Should namespace classes intelligently What I'm looking for might be more of a library of utilities, as I really don't want to be restricted by the framework in what I can and can not do. I have my own small library of core classes that take care of business logic, and I will most likely want to integrate those with the new framework as well. Thanks!

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  • Searching for patterns to create a TCP Connection Pool for high performance messaging

    - by JoeGeeky
    I'm creating a new Client / Server application in C# and expect to have a fairly high rate of connections. That made me think of database connection pools which help mitigate the expense of creating and disposing connections between the client and database. I would like to create a similar capability for my application and haven't been able to find any good examples of how to apply this pattern. Do I really need to spin up an instance of a TcpClient every time I want to send a message to the server and receive a receipt message? Each connection is expected to transport between 1-5KB with each receiving a 1KB response message. I realize this question is somewhat vague, but I am starting from scratch so I am open to suggestions. Even if that means my suppositions are all wrong.

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  • transforming binary data using ssis and sql server 2008

    - by Rick
    Hello All - I have a task to import/transform and extract zipped binary files that contain both text data as well as embeded binary data. Within the data is data that is relational in nature and needs to be processed into a defined database structure. Currently I have a C# single threaded app that essentially grabs all the files from the directory (currently there is 13K files of varying sizes) and extracts the data on a single thread line by line inserts to the database. As you could imagine this is a very slow process and unacceptable. There are several different parsing routines used depending on the header record in the file. There are potentially upto a million rows per file when all the data is extracted to the row level of detail. Follow on task is to parse those rows into their appropriate tables based on is content. i.e. the textual content has to be parsed further into "buckets" of like data in the database. That about sums up the big picture. Now for the problem task list. How do i iterate through a packet of data using SSIS? In the app the file is decompressed and then is parsed using streams data type and byte arrays and is routed to the required parsing routine based on the header data of each packet. There is bit swapping involved as well. Should i wrap up the app code into a script task(s) and let it do the custom processing? The data is seperated by year and the sql server tables is partitioned by year as well. I need to be able to "catch" bad file data as well and process by hand most likely. Should i simply load the zipped file to sql as a blob and parse the file with T-SQL? Would that be multi threaded if done that way? Not sure how to do the parsing in tsql that is involved here. Which do you think would be faster? Potentially the data that is currently processed via files could come to us via a socket. Can SSIS collect that data in real time? How would i go about setting that up? Processing these new files from the directorys will become a daily task. I can manage the data once i get it to sql server. Getting it there in a timely fashion seems to be the long pole in the tent for me. I would appreciate any comments or suggestions from the group. Rick

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  • Is SEO knowledge important for web developers?

    - by splattne
    Looking for some SEO (Search engine optimization) questions on Stackoverflow, I saw ambivalent reactions to these questions. Some were closed as "not programming related" or were downvoted, others were answered and got upvoted. It seems that many developers think SEO was something "dirty" or belonged in the realm of spam. IMHO designing for search engines and practising SEO techniques adds important value to the final product like, for example, a good user interface. Should SEO really be left to specialized non-programmers? Shouldn't web developers have profound SEO knowledge? Or is it okay to apply SEO as a post-development process?

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  • OOP function and if statement

    - by Luke
    Not sure if I can ask two questions? If i run the following function in my database class function generateUserArray() { $u = array(); $result = $this->selectAllUsers(); while( $row=mysql_fetch_assoc($result)) { $u[] = $row['username']; } return $u; } Would i call it like this? $u[] = $datebase->generateUserArray(); My second question, will this work: else if($database->addLeagueInformation($subname, $subformat, $subgame, $subseason, $subwindow, $subadmin, $subchampion, $subtype) && $databases->addLeagueTable($name) && $_SESSION['players'] == $subplayers && $comp_name = "$format_$game_$name_$season" && $_SESSION['comp_name'] = $comp_name) Thankyou

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  • Can SQLAlchemy DateTime Objects Only Be Naive?

    - by Sean M
    I am working with SQLAlchemy, and I'm not yet sure which database I'll use under it, so I want to remain as DB-agnostic as possible. How can I store a timezone-aware datetime object in the DB without tying myself to a specific database? Right now, I'm making sure that times are UTC before I store them in the DB, and converting to localized at display-time, but that feels inelegant and brittle. Is there a DB-agnostic way to get a timezone-aware datetime out of SQLAlchemy instead of getting naive datatime objects out of the DB?

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  • Binary search of unaccesible data field in ldap from python

    - by EricR
    I'm interested in reproducing a particular python script. I have a friend who was accessing an ldap database, without authentication. There was a particular field of interest, we'll call it nin (an integer) for reference, and this field wasn't accessible without proper authentication. However, my friend managed to access this field through some sort of binary search (rather than just looping through integers) on the data; he would check the first digit, check if it was greater or less than the starting value, he would augment that until it returned a true value indicating existence, adding digits and continuing checking until he found the exact value of the integer nin. Any ideas on how he went about this? I've access to a similarly set up database.

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  • Querying datatable to get rows with a certain value in the first column

    - by user1776590
    I am currently using the code below and am wondering if it would be possible to query based on an entry value. At the moment it returns the number of rows that have been defined. var q = sqlData.AsEnumerable().Take(2); This data comes in from a database and is imputed into the table but at the moment it only returns database data into the datatable and allows me to select the first two rows and I was wondering if I can query the data table so that I can get the rows that I require based on an index in the actual table itself (e.g. in the table I find five rows and query this information out).

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  • Using property file in hibernate mapping

    - by Zoltan Hamori
    Hi, I have a two nodes environment using the same database. In the database there is a resource table like RESOURCE_ID, CODE, NODE The content of the NODE column can be 1 or 2 depending on which node can use it. As I need to deploy the same ear to the two nodes, I would like to map this table like this: <hibernate-mapping> <class name="ResourceVO" table="RESOURCE" dynamic-update="true" optimistic-lock="dirty" where="NODE=${node.value}" > I would like to store the node.value property on the file system, so the instances could identify which resource to use. Is it possible in hibernate?

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  • Why is django admin not accepting Nullable foreign keys?

    - by p.g.l.hall
    Here is a simplified version of one of my models: class ImportRule(models.Model): feed = models.ForeignKey(Feed) name = models.CharField(max_length=255) feed_provider_category = models.ForeignKey(FeedProviderCategory, null=True) target_subcategories = models.ManyToManyField(Subcategory) This class manages a rule for importing a list of items from a feed into the database. The admin system won't let me add an ImportRule without selecting a feed_provider_category despite it being declared in the model as nullable. The database (SQLite at the moment) even checks out ok: >>> .schema ... CREATE TABLE "someapp_importrule" ( "id" integer NOT NULL PRIMARY KEY, "feed_id" integer NOT NULL REFERENCES "someapp_feed" ("id"), "name" varchar(255) NOT NULL, "feed_provider_category_id" integer REFERENCES "someapp_feedprovidercategory" ("id"), ); ... I can create the object in the python shell easily enough: f = Feed.objects.get(pk=1) i = ImportRule(name='test', feed=f) i.save() ...but the admin system won't let me edit it, of course. How can I get the admin to let me edit/create objects without specifying that foreign key?

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  • SQL Access INSERT INTO Autonumber Field

    - by KrazyKash
    I'm trying to make a visual basic application which is connected to a Microsoft Access Database using OLEDB. Inside my database I have a user table with the following layout ID - Autonumber Username - Text Password - Text Email - Text To insert data into the table I use the following query INSERT INTO Users (Username, Password, Email) VALUES ('004606', 'Password', '[email protected]') However I seem to get an error with this statement and according to VB it's a syntax error. But then I tried to use the following query INSERT INTO Users (Username) Values ('004606') This query seemed to work absolutely fine... So the problem is I can insert into just one field but not all 3 (excluding the ID field because it's an autonumber). Any help would be appreciated, Thanks

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  • Linking Excel and Access

    - by Mel
    I run a sports program where i have a master roll of who is in which class in excel. I want to link this to a database in access that stores the other information about each athlete, e.g. address, parents name, school, medical details. I want to be able to add names to class in the excel speadsheet and have this automatically generate a record for that person in access. There also needs to be some failsafe for athletes that are in multiple classes. I was also doing class roles as pivot tables out of the access database so i need to code for classes and also have this allow for athletes in multiple classes/disciplines.

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  • Query DNSBL or other block lists using PHP

    - by 55skidoo
    Is there any way to use PHP code to query a DNSBL (block list) provider and find out if the IP address submitted is a bad actor? I would like to take an existing IP address out of a registration database, then check whether it's a known block-listed IP address by performing a lookup on it, then if it's a blacklisted, do an action on it (such as, delete entry from registration database). Most of the instructions I have seen assume you are trying to query the blocklist via a mail server, which I can't do. I tried querying via web browser by typing in queries such as "58.64.xx.xxx.dnsbl.sorbs.net" but that didn't work.

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  • MS Access (2010) Enable Design View

    - by Tim GONELLA
    I downloaded the Access template below for doing a home inventory: http://office.microsoft.com/en-us/templates/results.aspx?qu=home%20inventory&ex=1&queryid=0d245f2a%2Dacdc%2D4161%2D92c8%2D8ba16a52ab32&AxInstalled=1&c=0#ai:TC101918100| The design view is not visible, which is a bit of a nuisance. Things I've tried: 1) In options/options/current database/ the check boxes (enable layout view & enable design changes for tables in Datasheet view) are both greyed out. 2) I've unblocked the file using Right-Click-Properties. 3) I've tried copying/exporting the objects to another database. But can only copy/export the tables. 4) I've tried holding shift when opening the DB. 5) Enabling all trust permissions etc. None of these work Does anybody have any suggestions. (I'm using Office 2010) Thanks

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  • php paypal ipn membership error

    - by aleksander haugas
    hello I integrated the membership subscription in the website, but I fail to insert data to the database. checking out all the function I make a txt file with php with data and generates me correctly. but I can not verify any data and less insert. <?php // read the post from PayPal system and add 'cmd' $req = 'cmd=_notify-validate'; foreach ($_POST as $key => $value) { $value = urlencode(stripslashes($value)); $req .= "&$key=$value"; } // Post back to PayPal system to validate $header .= "POST /cgi-bin/webscr HTTP/1.0\r\n"; $header .= "Content-Type: application/x-www-form-urlencoded\r\n"; $header .= "Content-Length: " . strlen($req) . "\r\n\r\n"; $fp = fsockopen ('ssl://www.paypal.com', 443, $errno, $errstr, 30); // Assign posted variables to local variables $item_name = $_POST['item_name']; $item_number = $_POST['item_number']; $payment_status = $_POST['payment_status']; $payment_amount = $_POST['mc_gross']; $payment_currency = $_POST['mc_currency']; $txn_id = $_POST['txn_id']; $receiver_email = $_POST['receiver_email']; $payer_email = $_POST['payer_email']; $user_id = $_POST['custom']; //Here i make the txt file and it works correctly //but after this does not work or make a txt file //Insert and update data if (!$fp) { // HTTP ERROR } else { fputs ($fp, $header . $req); while (!feof($fp)) { $res = fgets ($fp, 1024); if (strcmp ($res, "VERIFIED") == 0) { //Verificamos el estado del pedido if ($payment_status == 'Completed') { $txn_id_check = mysql_query("SELECT Transaction_ID FROM ".$db_table_prefix."Users_Payments WHERE Transaction_ID='".$txn_id."'"); if (mysql_num_rows($txn_id_check) !=1) { //Si el pago se ha realizado al dueño especificado y coincide con el dueño if ($receiver_email == $website_Payment_Email) { //Tipo de cuenta segun pagado if ($payment_amount == '10.00' && $payment_currency == 'EUR') { //add txn_id to database $log_query = mysql_query("INSERT INTO `".$db_table_prefix."Users_Payments` VALUES ('','".$txn_id."','".$payer_email."')"); //update premium to 3 $update_premium = mysql_query("UPDATE ".$db_table_prefix."Users SET Group_ID='3' WHERE User_ID='".$user_id."'"); } } } } } else if (strcmp ($res, "INVALID") == 0) { // log for manual investigation } } fclose ($fp); } ?> I call this file with require_once () with the connection to the database any ideas? thanks

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