Search Results

Search found 18865 results on 755 pages for 'distinct values'.

Page 511/755 | < Previous Page | 507 508 509 510 511 512 513 514 515 516 517 518  | Next Page >

• What's the standard behaviour for an out parameter when a TryXxxx method returns false?

  - by Matt Lacey

  Assuming a method with the following signature bool TryXxxx(object something, out int toReturn) What is it acceptable for toReturn to be if TryXxxx returns false? In that it's infered that toReturn should never be used if TryXxxx fails does it matter? If toReturn was a nulable type, then it would make sense to return null. But int isn't nullable and I don't want to have to force it to be. If toReturn is always a certain value if TryXxxx fails we risk having the position where 2 values could be considered to indicate the same thing. I can see this leading to potential possible confusion if the 'default' value was returned as a valid response (when TryXxxx returns true). From an implementation point if view it looks like having toReturn be a[ny] value is easiest, but is there anything more important to consider?

  Read the article

• update a column in input file by taking value from Database in perl.

  - by Rahul Singh

  input file: 1,a,USA,, 2,b,UK,, 3,c,USA,, i want to update the 4th column in the input file from taking values from one of the table. my code looks like this: my $customer_dbh = DBI-connect("DBI:Oracle:$INST", $USER, $PASS ) or die "Couldn't connect to datbase $INST"; my $cust_smh; print "connected \n "; open FILE , "+$input_file" or die "can't open the input file"; print "echo \n"; while(my $line=) { my @line_a=split(/\,/,$line); my $customer_id=$line_a[3]; print "$customer_id\n"; $cust_smh = $customer_dbh-prepare("SELECT phone_no from book where number = $line_a[0]"); $cust_smh-execute() or die "Couldn't execute stmt, error : $DBI::errstr"; my $number = $cust_smh-fetchrow_array(); $line_a[3]=$number; }

  Read the article

• Validating Column Data Stored as CSV Against Another Table

  - by Jakkwylde

  I wanted to see what some suggested approaches would be to validate a field that is stored as a CSV against a table containing appropriate values. Althought it would be desired, it is NOT an option to split the CSV list into another related table. In the example data below I would be trying to capture the code 99 for widget A. Below is an example data representation. Table: Widgets WidgetName WidgetCodeList A 1, 2, 3 B 1 C 2, 3 D 99 Table: WidgetCodes WidgetCode 1 2 3 An earlier approach was to query the CSV column as rows using various string manipulations and CONNECT_BY_LEVEL however the performance was not acceptible.

  Read the article

• How to sanitize log messages in Log4j to save them in database

  - by Rafael

  Hello, I'm trying to save log messages to a central database. In order to do this, I configured the following Appender in log4j's xml configuration: <appender name="DB" class="org.apache.log4j.jdbc.JDBCAppender"> <param name="URL" value="jdbc:postgresql://localhost/logging_test" /> <param name="user" value="test_user" /> <param name="password" value="test_password" /> <param name="sql" value="INSERT INTO log_messages ( log_level, message, log_date ) VALUES ( '%p', '%m', '%d{yyyy-MM-dd HH:mm:ss}' )" /> </appender> This works fine, except some of the messages contain ', and then the appender fails. Is there an easy way to do this?

  Read the article

• Basic Conditional Checking for IF statements in C

  - by ZaZu

  Hi there, Can someone please explain what really goes on in this code ? If I put the AND statement, the message wont show if values are less than 0 or greater than 10 ... I think I must use 1 0 logic to work this out right ? I just need someone to briefly explain it please. #include<stdio.h> main(){ puts("enter number"); scanf("%d",num); if(num<0 || num >10) puts("yay"); } How is that IF statement different when AND is put : #include<stdio.h> main(){ puts("enter number"); scanf("%d",num); if(num<0 && num >10) puts("yay"); } Thanks !!

  Read the article

• Multiple LIKE in SQL

  - by ninumedia

  I wanted to search through multiple rows and obtain the row that contains a particular item. The table in mySQL is setup so each id has a unique list (comma-delimited) of values per row. Ex: id | order 1 | 1,3,8,19,34,2,38 2 | 4,7,2,190,38 Now if I wanted to pull the row that contained just the number 19 how would I go about doing this? The possibilities I could figure in the list with a LIKE condition would be: 19, ,19 ,19, I tried the following and I cannot obtain any results, Thank you for your help! SELECT * FROM categories WHERE order LIKE '19,%' OR '%,19%' OR '%,19%' LIMIT 0 , 30

  Read the article

• core-plot and NSDate (iPhone)

  - by Urizen

  I wish to plot a line graph where the x-axis is defined as a number of days between two dates and the y-axis is a value that varies on each of the days. I can plot the y values as an NSNumber but I have no idea how to set the ranges and the markup on the x-axis. I have looked at the date example in the "examples" directory of the core-plot distribution but have found it a little confusing. Does anyone know of a tutorial, or code sample, which might asist me in this regard? Thank you in advance.

  Read the article

• What preferred way to reconcile keyCode/charCode across browsers?

  - by Drew Turner

  Based on the properties of the keydown event I would like to ascertain what the current charCode are? Example. For the keydown event when the NumPad0, D0, and Colon key is pressed I would like to know what the associated charcode is. Currently I have a map that contains the charcode associated with that keyCode or use the current if charCode is not specified. keyCode = { Colon: 186, D0: 48, NumPad0: 96, }; charCodes = { 186: 59, 96: 48, }; shiftCharCodes = { 186: 58, 48: 41 }; Also in certain cases the keyCodes are different accross browsers? Example. The keydown event has different keyCode values across browsers. Colon Key (:/;) - keyCode is 59 on firefox - keyCode is 186 on IE/safari For more information http://www.quirksmode.org/js/keys.html

  Read the article

• Worked Example of Digital Signature Algorithm

  - by drelihan

  Hi Folks, Does anybody have a DSA worked example with simple values on how to calculate r,s and verify v == r. As this standard has been around awhile and is implemented in librarys e.g. the Java Cryptography Extension I'm finding it very hard to find an example of how the algorithm works. Compute r=(gk mod p) mod q Compute s=(k-1 * (x * r + i)) mod q Verifying a signature; again i is the input, and (r,s) is the signature. u1 = (s-1 * i) mod q u2 = (s-1 * r) mod q v = ((gu1 * yu2) mod p) mod q If v equals r, the signature is valid. Thanks,

  Read the article

• How do I make this ASP.NET MVC controller more testable?

  - by Ragesh

  I have a controller that overrides OnActionExecuting and does something like this: protected override void OnActionExecuting(ActionExecutingContext filterContext) { base.OnActionExecuting(filterContext); string tenantDomain = filterContext.RouteData.Values["tenantDomain"] as string; if (!string.IsNullOrWhiteSpace(tenantDomain)) { using (var tx = BeginTransaction()) { this.Tenant = repo.FindOne(t => t.Domain == tenantDomain); } } } Tenant is a protected property with a private setter. The class itself is an abstract base controller that my real controllers derive from. I have code in other controllers that looks a lot like this: if (Tenant == null) { // Do something } else { // Do something else } How do I test this code? What I need to do is to somehow set the Tenant property, but I can't because: It's a protected property, and It has a private setter Changing the visibility of Tenant doesn't "feel" right. What are my alternatives to unit test my derived controllers?

  Read the article

• Storing object as a column in LINQ

  - by Alex

  Hello, i have some class which constructs itself from string, like this: CurrencyVector v = new CurrencyVector("10 WMR / 20 WMZ"); it's actually a class which holds multiple currency values, but it does not matter much. I need to change type of column in my LINQ table (in vs 2010 designer) from String to that class, CurrencyVector. If i do it - i get runtime error when LINQ runtime tries to cast String as CurrencyVector (when populating the table from database). Adding IConvertible did not help. I wrapped these columns in properties, but it's ugly and slow solution. Searching internet gave no results.

  Read the article

• Reading PGP key information

  - by calccrypto

  can someone show a description of the information of what a pgp looks like if only the descriptions were there but not the actual information? something like (i dont remember if the values are correct): packet-type[4 bits], total length in bytes[16 bits], packet version type [4 bits], creation-time[32 bits], encryption-algorithm[8 bits], ...,etc,etc ive tried to understand rfc4880, but its tedious and confusing. so far, i am think i have extracted the 4 i wrote above, but i cant seem to get the rest of the information out. can anyone help? i know i can just find some pgp program, but the whole point of this is to allow me to learn how those programs work in the first place

  Read the article

• Parse a json(?) string using php

  - by passatgt

  I have a string, more specifically, this one: a:16:{s:9:"pseudonym";O:16:"SimpleXMLElement":0:{}s:14:"parallel_title";O:16:"SimpleXMLElement":0:{}s:9:"title_var";O:16:"SimpleXMLElement":0:{}s:6:"series";O:16:"SimpleXMLElement":0:{}s:9:"vol_title";O:16:"SimpleXMLElement":0:{}s:9:"reference";O:16:"SimpleXMLElement":0:{}s:10:"bound_with";O:16:"SimpleXMLElement":0:{}s:15:"general_remarks";O:16:"SimpleXMLElement":0:{}s:6:"copies";O:16:"SimpleXMLElement":1:{i:0;s:1:"1";}s:11:"remarks_BPH";O:16:"SimpleXMLElement":0:{}s:3:"ICN";O:16:"SimpleXMLElement":1:{i:0;s:4:"neen";}s:10:"provenance";O:16:"SimpleXMLElement":0:{}s:7:"binding";O:16:"SimpleXMLElement":0:{}s:10:"size_hxwxd";O:16:"SimpleXMLElement":0:{}s:6:"BookID";O:16:"SimpleXMLElement":1:{i:0;s:4:"6271";}s:5:"repro";O:16:"SimpleXMLElement":0:{}} Is it possible to parse this string somehow? I need to display the keys and values in a list. I tried to use json_decode but it not returns anything, even with the second true parameter(json_decode($string,true))

  Read the article

• form serialize problem

  - by ZX12R

  I have a form. I am trying to validate it through AJAX GET requests. So i am trying to send the field values in the GET request data. $('#uxMyForm').serialize(); the problem it is returning something undecipherable. I have used serialize before. This is totally bizzare. the return value of serialize is authenticity_token=oRKIDOlPRqfnRehedcRRD7WXt6%2FQ0zLeQqwIahJZJfE%3D&customer%5BuxName%5D=&customer%5BuxEmail%5D=&customer%5BuxResidentialPhone%5D=&customer%5BuxMobilePhone%5D=&customer%5BuxDateOfBirth%5D=&customer%5BuxAddress%5D=&customer%5BuxResidentialStatus%5D= i have no idea how to use this. Thanks

  Read the article

• Is there performance to be gained by moving storage allocation local to a member function to its cla

  - by neuviemeporte

  Suppose I have the following C++ class: class Foo { double bar(double sth); }; double Foo::bar(double sth) { double a,b,c,d,e,f a = b = c = d = e = f = 0; /* do stuff with a..f and sth */ } The function bar() will be called millions of times in a loop. Obviously, each time it's called, the variables a..f have to be allocated. Will I gain any performance by making the variables a..f members of the Foo class and just initializing them at the function's point of entry? On the other hand, the values of a..f will be dereferenced through this-, so I'm wondering if it isn't actually a possible performance degradation. Is there any overhead to accessing a value through a pointer? Thanks!

  Read the article

• Modifying a MySQL database on a Ruby on Rails install

  - by James W

  Hello, sorry if this questions is overly basic or has been asked before but I simply cannot figure it out. On my Ruby on Rails site, I have a controller that accesses the fields of a table in my database and displays their "Name" field as a drop-down menu in one of my views. My problem is I need to change the options of that dropdown menu so I need a way to get into the MySQL database and change the values of those fields. Anyone know of a way to do this? It would be much appreciated. Thank you.

  Read the article

• does a switch idiom make sense in this case?

  - by the ungoverned

  I'm writing a parser/handler for a network protocol; the protocol is predefined and I am writing an adapter, in python. In the process of decoding the incoming messages, I've been considering using the idiom I've seen suggested elsewhere for "switch" in python: use a hash table whose keys are the field you want to match on (a string in this case) and whose values are callable expressions: self.switchTab = { 'N': self.handleN, 'M': self.handleM, ... } Where self.handleN, etc., are methods on the current class. The actual switch looks like this: self.switchTab[selector]() According to some profiling I've done with cProfile (and Python 2.5.2) this is actually a little bit faster than a chain of if..elif... statements. My question is, do folks think this is a reasonable choice? I can't imagine that re-framing this in terms of objects and polymorphism would be as fast, and I think the code looks reasonably clear to a reader.

  Read the article

• How to deal with constructor argument names?

  - by Bane

  Say I have a class that has some properties, like x, y, width and height. In its constructor, I couldn't do this: class A { public: A(int, int, int, int); int x; int y; int width; int height; }; //Wrong and makes little sense name-wise: A::A(int x, int y, int width, int height) { x = x; y = y; width = width; height = height; } First of all, this doesn't really make sense. Second, x, y, width and height become some weird values (-1405737648) when compiled using g++. It does work, however, if I append "a" to the argument names. What is the optimal way of solving these naming conflicts?

  Read the article

• Getting child elements that are related to a parent in same table

  - by Madawar

  I have the following database schema class posts(Base): __tablename__ = 'xposts' id = Column(Integer, primary_key=True) class Comments(Base): __tablename__ = 'comments' id = Column(Integer, primary_key=True) comment_parent_id=Column(Integer,unique=True) #comment_id fetches comment of a comment ie the comment_parent_id comment_id=Column(Integer,default=None) comment_text=Column(String(200)) Values in database are 1 12 NULL Hello First comment 2 NULL 12 First Sub comment I want to fetch all Comments and sub comments of a post using sqlalchemy and have this so far qry=session.query(Comments).filter(Comments.comment_parent_id!=None) print qry.count() Is there a way i can fetch the all the subcomments of a comment in a query i have tried outerjoin on the same table(comments) and it seemed stupid and it failed.

  Read the article

• Changing ylim (axis limits) drops data falling outside range. How can this be prevented?

  - by Alex Holcombe

  df <- data.frame(age=c(10,10,20,20,25,25,25),veg=c(0,1,0,1,1,0,1)) g=ggplot(data=df,aes(x=age,y=veg)) g=g+stat_summary(fun.y=mean,geom="point") Points reflect mean of veg at each age, which is what I expected and want to preserve after changing axis limits with the command below. g=g+ylim(0.2,1) Changing axis limits with the above command unfortunately causes veg==0 subset to be dropped from the data, yielding "Warning message: Removed 4 rows containing missing values (stat_summary)" This is bad because now the data plot (stat_summary mean) omits the veg==0 points. How can this be prevented? I simply want to avoid showing the empty part of the plot- the ordinate from 0 to .2, but not drop the associated data from the stat_summary calculation.

  Read the article

• How to avoid automatic renaming of sub signature parameters in visual basic 6.

  - by systempuntoout

  In Visual basic 6, i declare a sub like this: Private Sub test1(ByRef XmlFooOutput As String) ... End Sub after that, i declare another sub like the following one: Private Sub test2(ByRef xmlFooOutput As String) ... End Sub automagically, the first method is transformed in: Private Sub test1(ByVal xmlFooOutput As String) ... End Sub so the XmlFooOutput parameter is transformed in xmlFooOutput. This is a pretty dangerous feature because, method like those could be mapped to different XSL presentation files that read XML values through Xpath. So when test1 parameter is renamed, XSL bound to test1 method goes broken because Xpath point to XmlFooOuput but the correct value is now in xmlFooOutput. Is it possible to remove this weird feature? I'm using microsoft visual basic 6.0 (SP6). This question has some duplicate: http://stackoverflow.com/questions/1064858/stop-visual-basic-6-from-changing-my-casing http://stackoverflow.com/questions/248760/vb6-editor-changing-case-of-variable-names from what i see, there's no practical solution to disable this Intellisense evil feature.

  Read the article

• Cannot implicitly convert type ... to ... problem

  - by Younes

  I have this code: public static IEnumerable<dcCustomer> searchCustomer(string Companyname) { TestdbDataContext db = new TestdbDataContext(); IEnumerable<dcCustomer> myCustomerList = (from Customer res in db.Customers where res.CompanyName == Companyname select res); return myCustomerList; } And whatever i try i keep getting the convert error. Error 1 Cannot implicitly convert type 'System.Collections.Generic.IEnumerable<ConnectionWeb.Customer>' to 'System.Collections.Generic.IEnumerable<ConnectionWeb.DAL.dcCustomer>'. An explicit conversion exists (are you missing a cast?) \\srv01\home$\Z****\Visual Studio 2008\Projects\ConnectionWeb\ConnectionWeb\DAL\dcCustomer.cs 63 20 ConnectionWeb I want to try get myCustomerList to keep the values in an enumerator and return it.

  Read the article

• Scala Tuple Deconstruction

  - by dbyrne

  I am new to Scala, and ran across a small hiccup that has been annoying me. Initializing two vars in parallel works great: var (x,y) = (1,2) However I can't find a way to assign new values in parallel: (x,y) = (x+y,y-x) //invalid syntax I end up writing something like this: val xtmp = x+y; y = x-y; x = xtmp I realize writing functional code is one way of avoiding this, but there are certain situations where vars just make more sense. I have two questions: 1) Is there a better way of doing this? Am I missing something? 2) What is the reason for not allowing true parallel assignment?

  Read the article

• Model state inferno - how can Model.A be two different things at the same time?

  - by Martin

  I have this <%=Model.StartDate%> <%=Html.Hidden("StartDate", Model.StartDate)%> it outputs: 2010-05-11 11:00:00 +01:00 <input type="hidden" value="2010-03-17 11:00:00 +01:00" name="StartDate" id="StartDate"> What the... It's a paging mechanism so the hidden value was valid on the first page and I've been able to move forward to the next page. But since the values won't update properly it ends there. What do I need to do? Using firefox.

  Read the article

• programming question about numbers

  - by Syom

  it's a task, on which i think during whole day. i have four integer numbers a, b, c, d, and ineger x[1,40]. i must write a program, which can find the values of {a,b,c,d}, for which one of following equations is true for any (x<=40, x=1) x=a or x=b or x=a+b or x=a+b+c+d or x+a=c+d or x+a+b=c+d or ... x+a+b+c=d or ... it is very difficult to explain what i want to say. maybe the example will be helpful. example: if x=17, by {a=1,b=2,c=5,d=15} i can write x+a+b=c+d whole question is to present any x[1,40] by {a,b,c,d}. hope that you understand what i want to say, and thanks in advance

  Read the article

< Previous Page | 507 508 509 510 511 512 513 514 515 516 517 518  | Next Page >