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  • Django models: Use multiple values as a key?

    - by Rosarch
    Here is a simple model: class TakingCourse(models.Model): course = models.ForeignKey(Course) term = models.ForeignKey(Term) Instead of Django creating a default primary key, I would like to use both course and term as the primary key - taken together, they uniquely identify a tuple. Is this allowed by Django? On a related note: I am trying to represent users taking courses in certain terms. Is there a better way to do this? class Course(models.Model): name = models.CharField(max_length=200) requiredFor = models.ManyToManyField(RequirementSubSet, blank=True) offeringSchool = models.ForeignKey(School) def __unicode__(self): return "%s at %s" % (self.name, self.offeringSchool) class MyUser(models.Model): user = models.ForeignKey(User, unique=True) takingReqSets = models.ManyToManyField(RequirementSet, blank=True) takingTerms = models.ManyToManyField(Term, blank=True) takingCourses = models.ManyToManyField(TakingCourse, blank=True) school = models.ForeignKey(School) class TakingCourse(models.Model): course = models.ForeignKey(Course) term = models.ForeignKey(Term) class Term(models.Model): school = models.ForeignKey(School) isPrimaryTerm = models.BooleanField()

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  • ASP.NET, XSLT, extracting values from a CDATA section

    - by H4mm3rHead
    Hi,i have a small problem i have xome xml with a cdata section. This CDATA section contains fragments of HTMl. I would like to extract some of the data inside this CDATA element. Right now i have a XSLT transformation that outputs the rest of the document as HTMl, but i need only a small part of the CDATA HTML, not the entire part - e.g. a my Title tag. How to do this?

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  • Populating PHP list() with values in an array.

    - by Mike
    Hi, I have an array: $arr = array('foo', 'bar', 'bash', 'monkey', 'badger'); I want to have the elements in that array appear as the variables in my list(): list($foo, $bar, $bash, $monkey, $badger) = $data; Without actually specifying the variables, I tried; list(implode(",$", $arr)) = $data; and list(extract($arr)) = $data; But they don't work, I get: Fatal error: Can't use function return value in write context Does anyone have any idea whether this is possible? Cheers, Mike

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  • Getting parameters values blank and null when using custom wsdl in axis2

    - by Narendra
    Hi All, I am using axis2 for my web services creation. I want to user my own wsdl file instead of using generated wsdl file. When I am placing my own wsdl file in META-INF directory and deploying my web services they are deploying successfully. But the problem is when i try to test these web service using soapui it throwing null pointer exception. For example I am invoking following operations in soap ui. public String testWebService(String a, String b) { LogHelper.info("Value of a is:"+a); LogHelper.info("Value of b is :"+b); String c=a.trim()+b.Trim(); return "suceess" } output in console: value of a is: value of b is:null 19:58:47,781 ERROR [RPCMessageReceiver] Exception occurred while trying to invoke service method testWebService java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.axis2.rpc.receivers.RPCUtil.invokeServiceClass(RPCUtil.java:194) at org.apache.axis2.rpc.receivers.RPCMessageReceiver.invokeBusinessLogic(RPCMessageReceiver.java:102) at org.apache.axis2.receivers.AbstractInOutMessageReceiver.invokeBusinessLogic(AbstractInOutMessageReceiver.java:40) at org.apache.axis2.receivers.AbstractMessageReceiver.receive(AbstractMessageReceiver.java:114) at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:173) at org.apache.axis2.transport.http.HTTPTransportUtils.processHTTPPostRequest(HTTPTransportUtils.java:173) at org.apache.axis2.transport.http.AxisServlet.doPost(AxisServlet.java:142) at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190) at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92) at o...................................................... SO What i understand is i am getting value for a is black and value of b is null. Can any one give me any suggestions please. Thanks, Narendra

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  • SQL query mixing aggregated results and single values

    - by Paul Flowerdew
    I have a table with transactions. Each transaction has a transaction ID, and accounting period (AP), and a posting value (PV), as well as other fields. Some of the IDs are duplicated, usually because the transaction was done in error. To give an example, part of the table might look like: ID PV AP 123 100 2 123 -100 5 In this case the transaction was added in AP2 then removed in AP5. Another example would be: ID PV AP 456 100 2 456 -100 5 456 100 8 In the first example, the problem is that if I am analyzing what was spent in AP2, there is a transaction in there which actually shouldn't be taken into account because it was taken out again in AP5. In the second example, the second two transactions shouldn't be taken into account because they cancel each other out. I want to label as many transactions as possible which shouldn't be taken into account as erroneous. To identify these transactions, I want to find the ones with duplicate IDs whose PVs sum to zero (like ID 123 above) or transactions where the PV of the earliest one is equal to sum(PV), as in the second example. This second condition is what is causing me grief. So far I have SELECT * FROM table WHERE table.ID IN (SELECT table.ID FROM table GROUP BY table.ID HAVING COUNT(*) > 1 AND (SUM(table.PV) = 0 OR SUM(table.PV) = <PV of first transaction in each group>)) ORDER BY table.ID; The bit in chevrons is what I'm trying to do and I'm stuck. Can I do it like this or is there some other method I can use in SQL to do this? Edit 1: Btw I forgot to say that I'm using SQL Compact 3.5, in case it matters. Edit 2: I think the code snippet above is a bit misleading. I still want to mark out transactions with duplicate IDs where sum(PV) = 0, as in the first example. But where the PV of the earliest transaction = sum(PV), as in the second example, what I actually want is to keep the earliest transaction and mark out all the others with the same ID. Sorry if that caused confusion. Edit 3: I've been playing with Clodoaldo's solution and have made some progress, but still can't get quite what I want. I'm trying to get the transactions I know for certain to be erroneous. Suppose the following transactions are also in the table: ID PV AP 789 100 2 789 200 5 789 -100 8 In this example sum(PV) < 0 and the earliest PV < sum(PV) so I don't want to mark any of these out. If I modify Clodoaldo's query as follows: select t.* from t left join ( select id, min(ap) as ap, sum(pv) as sum_pv from t group by id having sum(pv) <> 0 ) s on t.id = s.id and t.ap = s.ap and t.pv = s.sum_pv where s.id is null This gives the result ID PV AP 123 100 2 123 -100 5 456 -100 5 456 100 8 789 100 3 789 200 5 789 -100 8 Whilst the first 4 transactions are ok (they would be marked out), the 789 transactions are also there, and I don't want them. But I can't figure out how to modify the query so that they're not included. Any ideas?

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  • PHP How to create real hex values from a string

    - by Piet
    Hi, I have a string with hexvalues that I use with sha1() echo sha1("\x23\x9A\xB9\xCB\x28\x2D\xAF\x66\x23\x1D\xC5\xA4\xDF\x6B\xFB\xAE\x00\x00\x00\x01"); ab94fcedf2664edfb9b291f85d7f77f27f2f4a9d now I have another string with the same value only not hex. $string2=strtoupper("239ab9cb282daf66231dc5a4df6bfbae00000001"); I want to convert this string so that it is read as above and that the sha1-value is the same as above. echo sha1(do_something($string2)); ab94fcedf2664edfb9b291f85d7f77f27f2f4a9d Does anybody know how to convert a string to real hexvalues? I've tried with pack, sprinft, hexdec, but nothing worked (couldn't find typecasting in hex) Thanks

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  • taking values from fields

    - by jagadeesh
    there is two table first table is pg_vendor_signup pg_vendor_signup id vendor_id name country_id secound table is pg_vendor_friends vid fid status pg_vendor_signup contain data is 1 3 ramu 381 2 4 raj 381 2 4 usha 381 3 4 krian 381 4 4 manu 381 4 9 aswin 381 pg_vendor_friends countain 1 9 4 0 1 9 3 0 i Want get all name where country id=381 and in pg_vendor_friends get status of table

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  • select similar values from mysql database

    - by mathew
    Hi I have several data s in MySQL database. In my table there is a column called rank. what I want is when some one enter a rank say 25 then the result should display names on similar(+ or -) ranks LIMIT to 10 from table. example mathew - 25 john - 26 joe - 25 stewart - 27 kelly - 24 brandon -23 magy - 22 .......etc. Thanks Mathew

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  • iPhone App not saving values to .plist file

    - by Trent
    Hey everyone. I am working on an app that displays a modal the first time the consumer uses it. I have a .plist file that will store the information I request once the Save button is pressed. I can read from the .plist file fine and when I run my save method it SEEMS to work fine but the .plist file is not updating. I'm not so sure of the problem here. I show the modal like this. - (void) getConsumerInfo { NSString *filePath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"consumer.plist"]; NSMutableDictionary *plistConsumerInfo = [[NSMutableDictionary alloc] initWithContentsOfFile:filePath]; NSString *hasAppeared = [plistConsumerInfo objectForKey:@"HasAppeared"]; if(hasAppeared != kHasAppeared) { ConsumerInfoViewController *tmpConsumerInfoVC = [[ConsumerInfoViewController alloc] initWithNibName:@"ConsumerInfoView" bundle:nil]; self.consumerInfoViewController = tmpConsumerInfoVC; [self presentModalViewController:consumerInfoViewController animated:YES]; [tmpConsumerInfoVC release]; } } This is called by the viewDidLoad method in the first view phone when the app is started. Within the consumerInfoViewController I have textfields that have data entered and when the Save button is pressed it calls this method. - (IBAction)saveConsumerInfo:(id)sender { NSString *filePath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"consumer.plist"]; NSMutableDictionary *plistDict = [[NSMutableDictionary alloc] initWithContentsOfFile:filePath]; NSString *tmpDiversName = txtDiversName.text; NSString *tmpLicenseType = txtLicenseType.text; NSString *tmpLicenseNum = txtLicenseNumber.text; NSString *tmpHasAppeared = @"1"; NSString *tmpNumJumps = @"3"; [plistDict setValue:[[NSString alloc] initWithFormat:@"%@", tmpDiversName] forKey:@"ConsumerName"]; [plistDict setValue:[[NSString alloc] initWithFormat:@"%@", tmpLicenseType] forKey:@"LicenseType"]; [plistDict setValue:[[NSString alloc] initWithFormat:@"%@", tmpLicenseNum] forKey:@"LicenseNumb"]; [plistDict setValue:[[NSString alloc] initWithFormat:@"%@", tmpNumJumps] forKey:@"NumJumps"]; [plistDict setValue:[[NSString alloc] initWithFormat:@"%d", tmpHasAppeared] forKey:@"Show"]; [plistDict writeToFile:filePath atomically: YES]; NSLog([[NSString alloc] initWithContentsOfFile:filePath]); [self dismissModalViewControllerAnimated:YES]; } This all runs fine with no hiccups but the file is never updated. I would like it to update so I can use this information throughout the app and update the flag so it will not show the view again once the data is entered. Please let me know if there is anymore information you need. Thanks in advance!

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  • Changing the admin edit window display values

    - by Henri
    I have a database table with e.g. a weight value e.g. CREATE TABLE product ( id SERIAL NOT NULL, product_name item_name NOT NULL, . . weight NUMERIC(7,3), -- the weight in kg . . CONSTRAINT PK_product PRIMARY KEY (id) ); This results is the model: class Product(models.Model): . weight = models.DecimalField(max_digits=7, decimal_places=3, blank=True, null=True) . I store the weight in kg's, i.e. 1 kg is stores as 1, 0.1 kg or 100g is stored as 0.1 To make it easier for the user, I display the weight in the Admin list display in grams by specifying: def show_weight(self): if self.weight: weight_in_g = self.weight * 1000 return '%0f' % weight_in_g So if a product weighs e.g. 0.5 kg and is stored in the database as such, the admin list display shows 500 Is there also a way to alter the number shown in the 'Change product' window. This window now shows the value extracted from the database, i.e. 0.5. This will confuse a user when I tell him with the help_text to enter the number in g, while seeing the number of kgs. Before saving the product I override save as follows: def save(self): if self.weight: self.weight = self.weight / 1000 This converts the number entered in grams to kgs.

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  • How to avoid serializing zero values with Simple Xml

    - by Bram Vandenbussche
    I'm trying to serialise an object using simple xml (http://simple.sourceforge.net/). The object setup is pretty simple: @Root(name = "order_history") public class OrderHistory { @Element(name = "id", required = false) public int ID; @Element(name = "id_order_state") public int StateID; @Element(name = "id_order") public int OrderID; } The problem is when I create a new instance of this class without an ID: OrderHistory newhistory = new OrderHistory(); newhistory.OrderID = _orderid; newhistory.StateID = _stateid; and I serialize it via simple xml: StringWriter xml = new StringWriter(); Serializer serializer = new Persister(); serializer.write(newhistory, xml); it still reads 0 in the resulting xml: <?xml version='1.0' encoding='UTF-8'?> <order_history> <id>0</id> <id_order>2</id_order> <id_order_state>8</id_order_state> </order_history> I'm guessing the reason for this is that the ID property is not null, since integers can't be null. But I really need to get rid of this node, and I'd rather not remove it manually. Any clues anyone?

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  • UITextFields losing values after UINavigationController activity

    - by Dan Ray
    This is going to be hard to demonstrate in code, but maybe you can picture it with me. I have a view that contains two UITextFields, "title" and "descr". That same view contains two UIButtons that push another controller onto the navController to get more detail from the user about the object we're assembling and ultimately uploading to my server. It appears that pushing another view on, doing something, and popping it back off results in the two UITextFields keeping their content VISUALLY, but the .text property of those fields becomes NULL. I've confirmed that if I do my two push-pop fields before filling in those UITextFields, I get my data when I upload, and if I do them in the opposite order, I don't. It LOOKS like there's data there, but I get nothing when I NSLog their .text properties. Is this normal? Do I need to just design around this? Or is this as weird as it seems, and I should be looking deeper at causes of this?

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  • Why might stable_sort be affecting my hashtable values?

    - by zebraman
    I have defined a struct ABC to contain an int ID, string NAME, string LAST_NAME; My procedure is this: Read in a line from an input file. Parse each line into first name and last name and insert into the ABC struct. Also, the struct's ID is given by the number of the input line. Then, push_back the struct into a vector masterlist. I am also hashing these to a hashtable defined as vector< vector , using first name and last name as keywords. That is, If my data is: Garfield Cat Snoopy Dog Cat Man Then for the keyword cash hashes to a vector containing Garfield Cat and Cat Man. I insert the structs into the hashtable using push_back again. The problem is, when I call stable_sort on my masterlist, my hashtable is affected for some reason. I thought it might be happening since the songs are being ordered differently, so I tried making a copy of the masterlist and sorting it and it still affects the hashtable though the original masterlist is unaffected. Any ideas why this might be happening?

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  • Wordpress databse insert() and update() - using NULL values

    - by pygorex1
    Wordpress ships with the wpdb class which handles CRUD operations. The two methods of this class that I'm interested in are the insert() (the C in CRUD) and update() (the U in CRUD). A problem arises when I want to insert a NULL into a mysql database column - the wpdb class escapes PHP null variables to empty strings. How can I tell Wordpress to use an actual MySQL NULL instead of a MySQL string?

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  • MS Excel - Macros for consolidating values from multiple sheets into a single sheet

    - by SpikETidE
    Hi everyone... Consider i have 4 workbooks with the following structure... 1. Main.xlsx Name Jan Feb Mar A B C 2. Jan.xlsx Name Jan A 3.3 B 6.4 C 5.3 3. Feb.xlsx Name Feb A 1.3 B 3.4 C 5.5 4. Mar.xlsx Name Mar A 1.3 B 3.4 C 5.5 I need to combine them like 1. Main.xlsx Name Jan Feb Mar A 3.3 1.3 1.3 B 6.4 3.4 3.4 C 5.3 5.5 5.5 And i need to automate the process... And i guess i can do this with macros...? Can anyone suggest some way with which i can proceed with the macro? Thanks for your time....

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  • computing hash values, integral types versus struct/class

    - by aaa
    hello I would like to know if there is a difference in speed between computing hash value (for example std::map key) of primitive integral type, such as int64_t and pod type, for example struct { int16_t v[4]; };. I know this is going to implementation specific, so my question ultimately pertains to gnu standard library. Thanks

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  • Bash script, read values from stdin pipe

    - by gmatt
    I'm trying to get bash to process data from stdin that gets piped it, but no luck, what I mean is none of the following work: echo "hello world" | test=($(< /dev/stdin)); echo test=$test test= echo "hello world" | read test; echo test=$test test= echo "hello world" | test=`cat`; echo test=$test test= where I want the output to be test=hello world. Note I've tried putting "" quotes around "$test" that doesn't work either.

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  • Matching a value to JSON array values in jquery

    - by chrism
    I have a JSON array that looks like this: ['Monkey','Cheetah','Elephant','Lizard','Spider'] I also have a text input. I want to test whether the value of the input upon 'blur' is also in the array and if it is do something. Knowing a bit of python I tried something like this: var existing_animals = ['Monkey','Cheetah','Elephant','Lizard','Spider'] $('input').blur(function() { user_animal = $(this).val() if (user_animal in existing_animals) { alert('Animal already exists!') } }); So, how rookie is my mistake?

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  • Query not returning rows in a table that don't have corresponding values in another [associative] ta

    - by Obay
    I have Table: ARTICLES ID | CONTENT --------------- 1 | the quick 2 | brown fox 3 | jumps over 4 | the lazy Table: WRITERS ID | NAME ---------- 1 | paul 2 | mike 3 | andy Table: ARTICLES_TO_WRITERS ARTICLE_ID | WRITER_ID ----------------------- 1 | 1 2 | 2 3 | 3 To summarize, article 4 has no writer. So when I do a "search" for articles with the word "the": SELECT a.id, a.content, w.name FROM articles a, writers w, articles_to_writers atw WHERE a.id=atw.article_id AND w.id=atw.writer_id AND content LIKE '%the%' article 4 does not show up in the result: ID | CONTENT | NAME ----------------------- 1 | the quick | paul How do I make article 4 still appear in the results even though it has no writers?

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  • Datatable add new column and values speed issue

    - by Cine
    I am having some speed issue with my datatables. In this particular case I am using it as holder of data, it is never used in GUI or any other scenario that actually uses any of the fancy features. In my speed trace, this particular constructor was showing up as a heavy user of time when my database is ~40k rows. The main user was set_Item of DataTable. protected myclass(DataTable dataTable, DataColumn idColumn) { this.dataTable = dataTable; IdColumn = idColumn ?? this.dataTable.Columns.Add(string.Format("SYS_{0}_SYS", Guid.NewGuid()), Type.GetType("System.Int32")); JobIdColumn = this.dataTable.Columns.Add(string.Format("SYS_{0}_SYS", Guid.NewGuid()), Type.GetType("System.Int32")); IsNewColumn = this.dataTable.Columns.Add(string.Format("SYS_{0}_SYS", Guid.NewGuid()), Type.GetType("System.Int32")); int id = 1; foreach (DataRow r in this.dataTable.Rows) { r[JobIdColumn] = id++; r[IsNewColumn] = (r[IdColumn] == null || r[IdColumn].ToString() == string.Empty) ? 1 : 0; } Digging deeper into the trace, it turns out that set_Item calls EndEdit, which brings my thoughts to the transaction support of the DataTable, for which I have no usage for in my scenario. So my solution to this was to open editing on all of the rows and never close them again. _dt.BeginLoadData(); foreach (DataRow row in _dt.Rows) row.BeginEdit(); Is there a better solution? This feels too much like a big giant hack that will eventually come and bite me. You might suggest that I dont use DataTable at all, but I have already considered that and rejected it due to the amount of effort that would be required to reimplement with a custom class. The main reason it is a datatable is that it is ancient code (.net 1.1 time) and I dont want to spend that much time changing it, and it is also because the original table comes out of a third party component.

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  • R how to find NA values after using addNA function

    - by screechOwl
    I have a data frame with a bunch of categorical variables. Some of them contain NA's and I use the addNA function to convert them to an explicit factor level. My problem comes when I try to treat them as NA's they don't seem to register. Here's my example data set and attempts to 'find' NA's: df1 <- data.frame(id = 1:200, y =rbinom(200, 1, .5), var1 = factor(rep(c('abc','def','ghi','jkl'),50))) df1$var2 <- factor(rep(c('ab c','ghi','jkl','def'),50)) df1$var3 <- factor(rep(c('abc','ghi','nop','xyz'),50)) df1[df1$var1 == 'abc','var1'] <- NA df1$var1 <- addNA(df1$var1) df1$isNaCol <- ifelse(df1$var1 == NA, 1, 0);summary(df1$isNaCol) df1$isNaCol <- ifelse(is.na(df1$var1), 1, 0);summary(df1$isNaCol) df1$isNaCol <- ifelse(df1$var1 == 'NA', 1, 0);summary(df1$isNaCol) df1$isNaCol <- ifelse(df1$var1 == '<NA>', 1, 0);summary(df1$isNaCol) Also when I type ??addNA I don't get any matches. Is this a gray-market function or something? Any suggestions would be appreciated.

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  • Querying tables based on other column values

    - by blcArmadillo
    Is there a way to query different databases based on the value of a column in the query? Say for example you have the following columns: id part_id attr_id attr_value_ext attr_value_int You then run a query and if the attr_id is '1' is returns the attr_value_int column but if attr_id is greater than '1' it joins data from another table based on the attr_value_ext.

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  • Select number of rows for each group where two column values makes one group

    - by Fábio Antunes
    I have a two select statements joined by UNION ALL. In the first statement a where clause gathers only rows that have been shown previously to the user. The second statement gathers all rows that haven't been shown to the user, therefore I end up with the viewed results first and non-viewed results after. Of course this could simply be achieved with the same select statement using a simple ORDER BY, however the reason for two separate selects is simple after you realize what I hope to accomplish. Consider the following structure and data. +----+------+-----+--------+------+ | id | from | to | viewed | data | +----+------+-----+--------+------+ | 1 | 1 | 10 | true | .... | | 2 | 10 | 1 | true | .... | | 3 | 1 | 10 | true | .... | | 4 | 6 | 8 | true | .... | | 5 | 1 | 10 | true | .... | | 6 | 10 | 1 | true | .... | | 7 | 8 | 6 | true | .... | | 8 | 10 | 1 | true | .... | | 9 | 6 | 8 | true | .... | | 10 | 2 | 3 | true | .... | | 11 | 1 | 10 | true | .... | | 12 | 8 | 6 | true | .... | | 13 | 10 | 1 | false | .... | | 14 | 1 | 10 | false | .... | | 15 | 6 | 8 | false | .... | | 16 | 10 | 1 | false | .... | | 17 | 8 | 6 | false | .... | | 18 | 3 | 2 | false | .... | +----+------+-----+--------+------+ Basically I wish all non viewed rows to be selected by the statement, that is accomplished by checking weather the viewed column is true or false, pretty simple and straightforward, nothing to worry here. However when it comes to the rows already viewed, meaning the column viewed is TRUE, for those records I only want 3 rows to be returned for each group. The appropriate result in this instance should be the 3 most recent rows of each group. +----+------+-----+--------+------+ | id | from | to | viewed | data | +----+------+-----+--------+------+ | 6 | 10 | 1 | true | .... | | 7 | 8 | 6 | true | .... | | 8 | 10 | 1 | true | .... | | 9 | 6 | 8 | true | .... | | 10 | 2 | 3 | true | .... | | 11 | 1 | 10 | true | .... | | 12 | 8 | 6 | true | .... | +----+------+-----+--------+------+ As you see from the ideal result set we have three groups. Therefore the desired query for the viewed results should show a maximum of 3 rows for each grouping it finds. In this case these groupings were 10 with 1 and 8 with 6, both which had three rows to be shown, while the other group 2 with 3 only had one row to be shown. Please note that where from = x and to = y, makes the same grouping as if it was from = y and to = x. Therefore considering the first grouping (10 with 1), from = 10 and to = 1 is the same group if it was from = 1 and to = 10. However there are plenty of groups in the whole table that I only wish the 3 most recent of each to be returned in the select statement, and thats my problem, I not sure how that can be accomplished in the most efficient way possible considering the table will have hundreds if not thousands of records at some point. Thanks for your help. Note: The columns id, from, to and viewed are indexed, that should help with performance. PS: I'm unsure on how to name this question exactly, if you have a better idea, be my guest and edit the title.

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  • Populate struct values with function argument

    - by adohertyd
    I am working on a program and part of it requires me to create a struct called DETAILS with the fields name, age, and height. I want to populate the record with data using a function argument. When I run my code I get compiler errors. I have put the errors in comment form beside the lines it is returned for but I can't fix them. Really could do with some help here guys thanks so much. Here is my code: #include <cstdlib> #include <iostream> #include <iomanip> using namespace std; const int LEN=100; struct DETAILS { char name[LEN]; int age; double height; }; person fillperson(struct DETAILS, char[LEN], int, double); int main() { struct person David; fillperson(David, "David Greene", 38, 180.0); //deprecated conversion from string constant to char * [-Wwrite-Strings] } person fillperson(struct DETAILS, char[LEN] name, int age, double height) //expected , or ... before 'name' { cin>>David.name>>name; cin>>David.age>>age; cin>>David.height>>height; cout<<"Done"<<endl; }

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