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  • Implementing a logging library in .NET with a database as the storage medium

    - by Dave
    I'm just starting to work on a logging library that everyone can use to keep track of any sort of system information while the user is running our application. The simplest example so far is to track Info, Warnings, and Errors. I want all plugins to be able to use this feature, but since each developer might have a different idea of what's important to report, I want to keep this as generic as possible. In the C++ world, I would normally use something like a stl::pair<string,string> to act as a key value pair structure, and have a stl::list of these to act as a "row" in the log. The log cache would then be a list<list<pair<string,string>>> (ugh!). This way, the developers can use a const string key like INFO, WARNING, ERROR to have a consistent naming for a column in the database (for SELECTing specific types of information). I'd like the database to be able to deal with any number of distinct column names. For example, John might have an INFO row with a column called USER, and Bill might have an INFO row with a column called FILENAME. I want the log viewer to be able to display all information, and if one report doesn't have a value for INFO / FILENAME, those fields should just appear blank. So one option is to use List<List<KeyValuePair<String,String>>, and the another is to have the log library consumer somehow "register" its schema, and then have the database do an ALTER TABLE to handle this situation. Yet another idea is to have a table that's just for key value pairs, with a foreign key that maps the key value pairs back to the original log entry. I obviously don't want logging to bog down the system, so I only lock the log cache to make a copy of the data (and remove the already-copied data), then a background thread will dump the information to the database. My specific questions regarding this are: Do you see any performance issues? In other words, have you ever tried something like this and found that certain things just don't work well in practice? Is there a more .NETish way to implement the key value pairs, other than List<List<KeyValuePair<String,String>>>? Even if there is a way to do #2 better, is the ALTER TABLE idea I proposed above a Bad Thing? Would you recommend multiple databases over a single one? I don't yet have an idea of how frequently the log would get written to, but we ideally would like to have lots of low level information. Perhaps there should be a DB with a fixed schema only for the low level stuff, and then another DB that's more flexible for reporting information back to users.

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  • Advice Please: SQL Server Identity vs Unique Identifier keys when using Entity Framework

    - by c.batt
    I'm in the process of designing a fairly complex system. One of our primary concerns is supporting SQL Server peer-to-peer replication. The idea is to support several geographically separated nodes. A secondary concern has been using a modern ORM in the middle tier. Our first choice has always been Entity Framework, mainly because the developers like to work with it. (They love the LiNQ support.) So here's the problem: With peer-to-peer replication in mind, I settled on using uniqueidentifier with a default value of newsequentialid() for the primary key of every table. This seemed to provide a good balance between avoiding key collisions and reducing index fragmentation. However, it turns out that the current version of Entity Framework has a very strange limitation: if an entity's key column is a uniqueidentifier (GUID) then it cannot be configured to use the default value (newsequentialid()) provided by the database. The application layer must generate the GUID and populate the key value. So here's the debate: abandon Entity Framework and use another ORM: use NHibernate and give up LiNQ support use linq2sql and give up future support (not to mention get bound to SQL Server on DB) abandon GUIDs and go with another PK strategy devise a method to generate sequential GUIDs (COMBs?) at the application layer I'm leaning towards option 1 with linq2sql (my developers really like linq2[stuff]) and 3. That's mainly because I'm somewhat ignorant of alternate key strategies that support the replication scheme we're aiming for while also keeping things sane from a developer's perspective. Any insight or opinion would be greatly appreciated.

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  • How to access fields in JSON object by index

    - by Stefan
    I know this isn't the best way to do it, but I have no other choice :( I have to access the items in JSONObject by their index. The standard way to access objects is to just wirte this[objectName] or this.objectName. I also found a method to get all the fields inside a json object: (for (var key in p) { if (p.hasOwnProperty(key)) { alert(key + " -> " + p[key]); } } (Soruce : Loop through Json object). However there is no way of accessing the JSONfields directly by a index. The only way I see right now, is to create an array, with the function above, get the fieldname by index and then get the value by fieldname. As far as I see it, the p (in our case the JSON file must be an iteratable array to, or else the foreach loop wouldn't work. How can I access this array directly? Or is it some kind of unsorted list? Regards, Stefan

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  • Make dictionary from list with python

    - by prosseek
    I need to transform a list into dictionary as follows. The odd elements has the key, and even number elements has the value. x = (1,'a',2,'b',3,'c') - {1: 'a', 2: 'b', 3: 'c'} def set(self, val_): i = 0 for val in val_: if i == 0: i = 1 key = val else: i = 0 self.dict[key] = val My solution seems to long, is there a better way to get the same results?

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  • Detecting GWT RichTextArea 'dirty' state

    - by David
    I want to detect when the contents of my GWT RichTextArea become 'dirty' (have been changed by the user) in order to enable a 'save' button accordingly. I suppose I could listen for key presses that are likely to have changed the contents; but browser support for key presses is notoriously quirky. I suppose I could, before editing begins, save the original contents in a variable, and upon key press, compare the current contents against that variable, but doing that on each key press is going to be really slow. Is there some neat way to achieve RichTextArea dirty-detection?

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  • How do i add a new object with suds?

    - by Jerome
    I'm trying to use suds but have so far been unsuccessful at figuring this out. Hopefully it's something simple that i'm missing. Any help would be highly appreciated. This is supposed to be the raw soap message that i need to achieve: <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:api="http://api.service.apimember.soapservice.com/"> <soapenv:Header/> <soapenv:Body> <api:insertOrUpdateMemberByObj> <token>t67GFCygjhkjyUy8y9hkjhlkjhuii</token> <member> <dynContent> <entry> <key>FIRSTNAME</key> <value>hhhhbbbbb</value> </entry> </dynContent> <email>[email protected]</email> </member> </api:insertOrUpdateMemberByObj> </soapenv:Body> </soapenv:Envelope> So i use suds to create the member object: member = client.factory.create('member') produces: (apiMember){ attributes = (attributes){ entry[] = <empty> } } How exactly do i append an 'entry'? I try this: member.attributes.entry.append({'key':'FIRSTNAME','value':'test'}) and that produces this: (apiMember){ attributes = (attributes){ entry[] = { value = "test" key = "FIRSTNAME" }, } } However, what i actually need is: (apiMember){ attributes = (attributes){ entry[] = (entry) { value = "test" key = "FIRSTNAME" }, } } How do i achieve this?

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  • Hibernate doesn't generate cascade

    - by Shervin
    Hi. I have a set hibernate.hbm2ddl.auto to create so that Hibernate creates the tables in mysql for me. However, it doesn't seem that hibernate correctly adds Cascade on the references in the table. It does however work when I for instance delete a row, and I have a delete cascade as hibernate annotation. So I guess that means that Hibernate reads the annoation on runtime, and perform cascading manually? Is that normal behavior? For instance: @Entity class Report { @OneToOne(cascade = CascadeType.ALL) public File getPdf() { return pdf; } } Here I have set cascade to ALL. However, when running show create table Report Report | CREATE TABLE `Report` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `pdf_id` bigint(20) DEFAULT NULL, PRIMARY KEY (`id`), KEY `FK91B14154FDE6543A` (`pdf_id`), CONSTRAINT `FK91B14154FDE6543A` FOREIGN KEY (`pdf_id`) REFERENCES `File` (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 | It doesn't say anything about cascading other then the foreign key. In my opinion, it should have added the ON DELETE CASCADE ON DELETE UPDATE

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  • How to instert child entities in JDO (Google App Engine) ?

    - by Kerem Pekçabuk
    How do i add a record to a child entity in the example below ? For example i have a Employee Record which is name is "Sam". how do i add 2 street adress for sam ? Guess i have a The Parent entity is Employee import java.util.List; // ... @Persistent(mappedBy = "employee") private List contactInfoSets; The Child key is Adress import com.google.appengine.api.datastore.Key; // ... imports ... @PersistenceCapable public class ContactInfo { @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) private Key key; @Persistent private String streetAddress; // ... }

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  • VB.NET: Dialog exits when enter pressed?

    - by Camilo Martin
    Hi all; My problem seems to be quite simple, but it's not working the intuitive way. I'm designing a Windows Forms Application, and there is a dialog that should NOT exit when the enter key is pressed, instead it has to validate data first, in case enter was pressed after changing the text of a ComboBox. I've tried by telling it what to do on KeyPress event of the ComboBox if e is the Enter key: Private Sub ComboBoxSizeChoose_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles ComboBoxSizeChoose.KeyPress If e.KeyChar = Convert.ToChar(Keys.Enter) Then Try TamanhoDaNovaFonte = Single.Parse(ComboBoxSizeChoose.Text) Catch ex As Exception Dim Dialogo2 As New Dialog2 Dialog2.ShowDialog() ComboBoxSizeChoose.Text = TamanhoDaNovaFonte End Try End If End Sub But no success so far. When the Enter key is pressed, even with the ComboBox on focus, the whole dialog is closed, returning to the previous form. The validation is NOT done at all, and it has to be done before exiting. In fact, I don't even want to exit on the form's enter KeyPress, the only purpose of the enter key on the whole dialog is to validate the ComboBox (but only when in focus, for the sake of an intuitive UI). I've also tried appending the validation to the KeyPress event of the whole dialog's form, if the key is Enter. NO SUCCESS! It's like my code wasn't there at all. What should I do? (Visual Studio 2008, VB.NET)

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  • Unallocated space with important data

    - by Chethan S.
    I used GParted to convert a primary partition to extended one after copying the data to another partition. After having the extended partition I moved the data back. To my utter shock after a restart I found out that the new extended partition did convert into "unallocated space". I tried installing testdisk. Testdisk could identify the partition as a primary partition and not the newly created extended partition. So what should I do now? I badly want the data back.

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  • How to shade a texture two different colors?

    - by Venesectrix
    To give an example of what I'm asking about, I'll use Saints Row 3 since I've been playing that lately. In that game you can customize your looks and your car's appearance a lot. Your coat can have a primary color and a trim color. Your car can have a primary color and a stripe color, etc. Is there just a single coat texture that is being shaded two different colors somehow or are they overlaying a transparent second texture for the trim/stripes that gets shaded differently? If it's just one texture I'd like to know how it's done. If it's two different textures it seems like it's a waste of space. The second texture would be the same size as the first one but mostly transparent if you just wanted to lay it on top of the first one. Or are they just carefully positioning a second, smaller texture so that it aligns properly with the first one?

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  • Entity Framework 4 Self Many-To-Many with Properties

    - by csharpnoob
    UPDATE: Solved by myself. Tricky but works. If you know a better solution, feel free to correct me. DESIGNER: CODE: Product product1 = new Product{key = "Product 1"}; sd.AddToProducts(product1); Product product2 = new Product{key = "Product 2"}; sd.AddToProducts(product2); Product product3 = new Product{key = "Product 3"}; ProductRelated pr = new ProductRelated(); pr.Products.Add(product1); pr.Products.Add(product2); product3.ProductRelateds.Add(pr); sd.AddToProducts(product3); CODE VIEW: foreach(var x in (from b in sd.Products select b)) { %><%=x.key %><br /> <% foreach (var y in x.ProductRelateds) { foreach (var k in y.Products) { %>- <%=k.key%><br /><%} } } OUTPUT Product1 Product2 Product3 - Product2 - Product1 QUESTION: Hi, i want to have a Self Reference for Releated Products on a Product Entity, something like here: http://my.safaribooksonline.com/9781430227038/modeling_a_many-to-many_comma_self-refer But i also want on the Many-To-Many Reference addional Properties like deleted, created etc. I tried to do it by another Entity "Related", but somehow it won't work. Does anyone had this Problem before? Is there any other Example? Thanks

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  • Mobile Safari Youtube opened via javascript

    - by Squeegy
    We have a youtube player embedded in a plage in Mobile Safari and it works great. But we need to be able to launch the youtube player by a means other than user tapping the video itself, for various reasons. So I am trying to figure out what event to trigger in javascript to make it happen with no luck. None of the following appear to work. var vid = document.getElementById('vid'); vid.click(); vid.onclick(); vid.ontouchend(); vid.ontouchstart(); vid.focus(); I tried to find an event handler added to the embedded object with this snippet, but didn't find anything. for (var key in vid) { if (typeof vid[key] == 'function') console.log(key +': '+ vid[key]); } Is this just so wrapped up in a custom plugin there is no way?

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  • Share java object between two forms using Spring IoC

    - by Vladimir
    I want to share java object between two forms using Spring IoC. It should acts like Registry: Registry.set("key", new Object()); // ... Object o = Registry.get("key"); // ... Registry.set("key", new AnotherObject()); // rewrite old object I tried this code to register bean at runtime: applicationContext.getBeanFactory().registerSingleton("key", object); but it does not allow to rewrite existing object (result code for checking and deleting existing bean is too complicated)... PS I am Java newbie, so mb I am doing it wrong and I should not use IoC at all... any help is appreciated...

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  • SQL Query to return maximums over decades

    - by Abraham Lincoln
    My question is the following. I have a baseball database, and in that baseball database there is a master table which lists every player that has ever played. There is also a batting table, which tracks every players' batting statistics. I created a view to join those two together; hence the masterplusbatting table. CREATE TABLE `Master` ( `lahmanID` int(9) NOT NULL auto_increment, `playerID` varchar(10) NOT NULL default '', `nameFirst` varchar(50) default NULL, `nameLast` varchar(50) NOT NULL default '', PRIMARY KEY (`lahmanID`), KEY `playerID` (`playerID`), ) ENGINE=MyISAM AUTO_INCREMENT=18968 DEFAULT CHARSET=latin1; CREATE TABLE `Batting` ( `playerID` varchar(9) NOT NULL default '', `yearID` smallint(4) unsigned NOT NULL default '0', `teamID` char(3) NOT NULL default '', `lgID` char(2) NOT NULL default '', `HR` smallint(3) unsigned default NULL, PRIMARY KEY (`playerID`,`yearID`,`stint`), KEY `playerID` (`playerID`), KEY `team` (`teamID`,`yearID`,`lgID`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; Anyway, my first query involved finding the most home runs hit every year since baseball began, including ties. The query to do that is the following.... select f.yearID, f.nameFirst, f.nameLast, f.HR from ( select yearID, max(HR) as HOMERS from masterplusbatting group by yearID )as x inner join masterplusbatting as f on f.yearID = x.yearId and f.HR = x.HOMERS This worked great. However, I now want to find the highest HR hitter in each decade since baseball began. Here is what I tried. select f.yearID, truncate(f.yearid/10,0) as decade,f.nameFirst, f.nameLast, f.HR from ( select yearID, max(HR) as HOMERS from masterplusbatting group by yearID )as x inner join masterplusbatting as f on f.yearID = x.yearId and f.HR = x.HOMERS group by decade You can see that I truncated the yearID in order to get 187, 188, 189 etc instead of 1897, 1885,. I then grouped by the decade, thinking that it would give me the highest per decade, but it is not returning the correct values. For example, it's giving me Adrian Beltre with 48 HR's in 2004 but everyone knows that Barry Bonds hit 73 HR in 2001. Can anyone give me some pointers?

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  • Glib hash table replace

    - by Robert
    I'm using GLib Hash Table. I'm trying to get the current value of the key that I found and then increment its value. I'm not quite sure how can I replace the existing value. typedef struct { gchar *key; guint my_int; } my_struct; char *v; v = g_hash_table_lookup(table, my_struct.key); if (v == NULL) g_hash_table_insert(table, g_strdup(my_struct.key), (gpointer)(my_struct.my_int)); else g_hash_table_replace() // here I'd like to do something like current_val+1 Any ideas will be appreciate it.

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  • What is wrong with my SQL syntax here?

    - by CT
    I'm trying to create a IT asset database with a web front end. I've gathered some data from forms using POST as well as one variable that had already written to a cookie. This is the first time I have tried to enter the data into the database. Here is the code: <?php //get data $id = $_POST['id']; $company = $_POST['company']; $location = $_POST['location']; $purchase_date = $_POST['purchase_date']; $purchase_order = $_POST['purchase_order']; $value = $_POST['value']; $type = $_COOKIE["type"]; $notes = $_POST['notes']; $manufacturer = $_POST['manufacturer']; $model = $_POST['model']; $warranty = $_POST['warranty']; //set cookies setcookie('id', $id); setcookie('company', $company); setcookie('location', $location); setcookie('purchase_date', $purchase_date); setcookie('purchase_order', $purchase_order); setcookie('value', $value); setcookie('type', $type); setcookie('notes', $notes); setcookie('manufacturer', $manufacturer); setcookie('model', $model); setcookie('warranty', $warranty); //checkdata //start database interactions // connect to mysql server and database "asset_db" mysql_connect("localhost", "asset_db", "asset_db") or die(mysql_error()); mysql_select_db("asset_db") or die(mysql_error()); // Insert a row of information into the table "asset" mysql_query("INSERT INTO asset (id, company, location, purchase_date, purchase_order, value, type, notes) VALUES('$id', '$company', '$location', '$purchase_date', $purchase_order', '$value', '$type', '$notes') ") or die(mysql_error()); echo "Asset Added"; // Insert a row of information into the table "server" mysql_query("INSERT INTO server (id, manufacturer, model, warranty) VALUES('$id', '$manufacturer', '$model', '$warranty') ") or die(mysql_error()); echo "Server Added"; //destination url //header("Location: verify_submit_server.php"); ?> The error I get is: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '', '678 ', 'Server', '789')' at line 2 That data is just test data I was trying to throw in there, but it looks to be the at the $value, $type, $notes. Here are the table create statements if they help: <?php // connect to mysql server and database "asset_db" mysql_connect("localhost", "asset_db", "asset_db") or die(mysql_error()); mysql_select_db("asset_db") or die(mysql_error()); // create asset table mysql_query("CREATE TABLE asset( id VARCHAR(50) PRIMARY KEY, company VARCHAR(50), location VARCHAR(50), purchase_date VARCHAR(50), purchase_order VARCHAR(50), value VARCHAR(50), type VARCHAR(50), notes VARCHAR(200))") or die(mysql_error()); echo "Asset Table Created.</br />"; // create software table mysql_query("CREATE TABLE software( id VARCHAR(50) PRIMARY KEY, software VARCHAR(50), license VARCHAR(50))") or die(mysql_error()); echo "Software Table Created.</br />"; // create laptop table mysql_query("CREATE TABLE laptop( id VARCHAR(50) PRIMARY KEY, manufacturer VARCHAR(50), model VARCHAR(50), serial_number VARCHAR(50), esc VARCHAR(50), user VARCHAR(50), prev_user VARCHAR(50), warranty VARCHAR(50))") or die(mysql_error()); echo "Laptop Table Created.</br />"; // create desktop table mysql_query("CREATE TABLE desktop( id VARCHAR(50) PRIMARY KEY, manufacturer VARCHAR(50), model VARCHAR(50), serial_number VARCHAR(50), esc VARCHAR(50), user VARCHAR(50), prev_user VARCHAR(50), warranty VARCHAR(50))") or die(mysql_error()); echo "Desktop Table Created.</br />"; // create server table mysql_query("CREATE TABLE server( id VARCHAR(50) PRIMARY KEY, manufacturer VARCHAR(50), model VARCHAR(50), warranty VARCHAR(50))") or die(mysql_error()); echo "Server Table Created.</br />"; ?> Running a standard LAMP stack on Ubuntu 10.04. Thank you.

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  • PHPMailer attachment type and size limit

    - by SomeoneS
    i have one form and i am using PHPMailer to send data from that form to my email. Users can send attachments as well, but i have one rpoblem: how to make PHPMailer to deny attachments larger than 2Mb and to allow only iamge attachments (no other types of documents)? This is code i using for multiply email attachments with PHPMailer: foreach(array_keys($_FILES['fileAttach']['name']) as $key) { $source = $_FILES['fileAttach']['tmp_name'][$key]; $filename = $_FILES['fileAttach']['name'][$key]; $mail->AddAttachment($source, $filename); }

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  • Error at JSON:Missing ] after element list

    - by dhivya
    var phoneBookTableValue = []; phoneBookTableValue.push({ "key":"1", "value":["3396,Accounting ,CCH,,,,","1"]}); phoneBookTableValue.push({ "key":"2", "value":["3284,Acute Care ,CCH,,,,","2"]}); phoneBookTableValue.push({ "key":"3", "value":["3265,Acute'Care East ,CCH,,,,","3"]}); When running the javascript file I get the error "missing ] after element list. Can U help me? PLZ!

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  • Http web request doesn't maintaining session.

    - by Pankaj Mishra
    Hello, I have program where i want to scrap some Useful study material for me. This site site maintaining session key and some other key also. If I trying to go nested page then it will throw me out and showing session out message. I unable to maintaining session key in web request class. so please give me some idea that how can i maintain session in web request class.

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  • Django unit testing: South-migrated DB works in MySQL, throws duplicate PK error in PostGreSQL. Am I

    - by unclaimedbaggage
    Hi folks, (Worth starting off with a disclaimer: I'm very new to PostGreSQL) I have a django site which involves a standard app/tests.py testing file. If I migrate the DB to MySQL (through South),, the tests all pass. However in PostGresQL, I'm getting the following error: IntegrityError: duplicate key value violates unique constraint "business_contact_pkey" Note this happens while unit testing only - the actual page runs fine in both MySQL & PostGresql. Really having a heckuva time figuring this one out. Anyone have ideas? Below are the Postgresql "\d business_contact" & offending tests.py method if they help. No changes made to either DB except the (same) South migrations Thanks first_name | character varying(200) | not null mobile_phone | character varying(100) | surname | character varying(200) | not null business_id | integer | not null created | timestamp with time zone | not null deleted | boolean | not null default false updated | timestamp with time zone | not null slug | character varying(150) | not null phone | character varying(100) | email | character varying(75) | id | integer | not null default nextval('business_contact_id_seq'::regclass) Indexes: "business_contact_pkey" PRIMARY KEY, btree (id) "business_contact_slug_key" UNIQUE, btree (slug) "business_contact_business_id" btree (business_id) Foreign-key constraints: "business_id_refs_id_772cc1b7b40f4b36" FOREIGN KEY (business_id) REFERENCES business(id) DEFERRABLE INITIALLY DEFERRED Referenced by: TABLE "business" CONSTRAINT "primary_contact_id_refs_id_dfaf59c4041c850" FOREIGN KEY (primary_contact_id) REFERENCES business_contact(id) DEFERRABLE INITIALLY DEFERRED TEST DEF: def test_add_business_contact(self): """ Add a business contact """ contact_slug = 'test-new-contact-added-new-adf' business_id = 1 business = Business.objects.get(id=business_id) postdata = { 'first_name': 'Test', 'surname': 'User', 'business': '1', 'slug': contact_slug, 'email': '[email protected]', 'phone': '12345678', 'mobile_phone': '9823452', 'business': 1, 'business_id': 1, } #Test to ensure contacts that should not exist are not returned contact_not_exists = Contact.objects.filter(slug=contact_slug) self.assertFalse(contact_not_exists) #Add the contact and ensure it is present in the DB afterwards """ contact_add_url = '%s%s/contact/add/' % (settings.BUSINESS_URL, business.slug) self.client.post(contact_add_url, postdata) added_contact = Contact.objects.filter(slug=contact_slug) print added_contact try: self.assertTrue(added_contact) except: formset = ContactForm(postdata) print formset.errors self.assertFalse(True, "Contact not found in the database - most likely, the post values in the test didn't validate against the form")

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  • Database Modelling - Conceptually different entities with near identical fields

    - by Andrew Shepherd
    Suppose you have two sets of conceptual entities: MarketPriceDataSet which has multiple ForwardPriceEntries PoolPriceForecastDataSet which has multiple PoolPriceForecastEntry Both different child objects have near identical fields: ForwardPriceEntry has StartDate EndDate SimulationItemId ForwardPrice MarketPriceDataSetId (foreign key to parent table) PoolPriceForecastEntry has StartDate EndDate SimulationItemId ForecastPoolPrice PoolPriceForecastDataSetId (foreign key to parent table) If I modelled them as separate tables, the only difference would be the foreign key, and the name of the price field. There has been a debate as to whether the two near identical tables should be merged into one. Options I've thought of to model this is: Just keep them as two independent, separate tables Have both sets in the one table with an additional "type" field, and a parent_id equalling a foreign key to either parent table. This would sacrifice referential integrity checks. Have both sets in the one table with an additional "type" field, and create a complicated sequence of joining tables to maintain referential integrity. What do you think I should do, and why?

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  • NHibernate / Fluent - Mapping multiple objects to single lookup table

    - by Al
    Hi all I am struggling a little in getting my mapping right. What I have is a single self joined table of look up values of certain types. Each lookup can have a parent, which can be of a different type. For simplicities sake lets take the Country and State example. So the lookup table would look like this: Lookups Id Key Value LookupType ParentId - self joining to Id base class public class Lookup : BaseEntity { public Lookup() {} public Lookup(string key, string value) { Key = key; Value = value; } public virtual Lookup Parent { get; set; } [DomainSignature] [NotNullNotEmpty] public virtual LookupType LookupType { get; set; } [NotNullNotEmpty] public virtual string Key { get; set; } [NotNullNotEmpty] public virtual string Value { get; set; } } The lookup map public class LookupMap : IAutoMappingOverride<DBLookup> { public void Override(AutoMapping<Lookup> map) { map.Table("Lookups"); map.References(x => x.Parent, "ParentId").ForeignKey("Id"); map.DiscriminateSubClassesOnColumn<string>("LookupType").CustomType(typeof(LookupType)); } } BASE SubClass map for subclasses public class BaseLookupMap : SubclassMap where T : DBLookup { protected BaseLookupMap() { } protected BaseLookupMap(LookupType lookupType) { DiscriminatorValue(lookupType); Table("Lookups"); } } Example subclass map public class StateMap : BaseLookupMap<State> { protected StateMap() : base(LookupType.State) { } } Now I've almost got my mappings set, however the mapping is still expecting a table-per-class setup, so is expecting a 'State' table to exist with a reference to the states Id in the Lookup table. I hope this makes sense. This doesn't seem like an uncommon approach when wanting to keep lookup-type values configurable. Thanks in advance. Al

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