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  • How to make an ambiguous call distinct in C++?

    - by jcyang
    void outputString(const string &ss) { cout << "outputString(const string& ) " + ss << endl; } void outputString(const string ss) { cout << "outputString(const string ) " + ss << endl; } int main(void) { //! outputString("ambigiousmethod"); const string constStr = "ambigiousmethod2"; //! outputString(constStr); } ///:~ How to make distinct call? EDIT: This piece of code could be compiled with g++ and msvc. thanks.

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  • ASP.NET C# Application Object Getters and Setters

    - by kellax
    I have had a hard time finiding a newbie friendly example of accessing Application Object. I have few things ( arrays ) i would like to store in Application Object to keep as persistant data for about 2h till AppRecycle Anyhow i know how to set an Application Object variable this way: // One way String[] users = new String[1000]; Application["users"] = users; // Another way Application.Add("users", users); However i do not know how to access these variables once in Application Object there is a Getter method Get however it requires int index and other one Contents which get's everything. Here i try to retrive my String[] array but gives me a error that i am trying to convert Object to String. String[] usersTable = Application["users"]; // Since this is an object i also tried Application.users but gives error

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  • How can I use "FOR UPDATE" with a JOIN on Oracle?

    - by tangens
    The answer to another SO question was to use this SQL query: SELECT o.Id, o.attrib1, o.attrib2 FROM table1 o JOIN ( SELECT DISTINCT Id FROM table1, table2, table3 WHERE ... ) T1 ON o.id = T1.Id Now I wonder how I can use this statement together with the keyword FOR UPDATE. If I simply append it to the query, Oracle will tell me: ORA-02014: cannot select FOR UPDATE from view Do I have to modify the query or is there a trick to do this with Oracle? With MySql the statement works fine.

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  • Save Sql Recordset into the Flat text file?

    - by mahesh kumar
    Hi, i need to dump my sql query result into the text file. i have created the following query, DECLARE @cmd VARCHAR(2048) SET @cmd = 'OSQL -localhost -CRN370 ' + ' -UCRN370 -PCRN370' + ' -Q"SELECT TOP 5 GageId FROM EwQMS370..msgages"' + ' -oc:\authors.txt' EXEC master..xp_cmdshell @cmd, NO_OUTPUT The above query created the text file authors.txt. But the content of the file shows the following error message " Error: Conflicting switches : -U and -E " Any help really appreciated

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  • ADO program to list members of a large group.

    - by AlexGomez
    Hi everyone, I'm attempting to list all the members in a Active Directory group using ADO. The problem I have is that many of these groups have over 1500 members and ADSI cannot handle more than 1500 items in a multi-valued attribute. Fortunately I came across Richard Muller's wonderful VBScript that handles more than 1500 members at http://www.rlmueller.net/DocumentLargeGroup.htm I modified his code as shown below so that I can list ALL the groups and its memberships in a certain OU. However, I'm keeping getting the exception shown below: "ADODB.Recordset: Item cannot be found in the collection corresponding to the requested name or ordinal." My program appears to get stuck at: strPath = adoRecordset.Fields("ADsPath").Value Set objGroup = GetObject(strPath) All I am doing above is issuing the query to get back a recordset consisting of the ADsPath for each group in the OU. It then walks through the recordset and grabs the ADsPath for the first group and store its in a variable named strPath; we then use the value of that variable to bind to the group account for that group. It really should work! Any idea why the code below doesn't work for me? Any pointers will be great appreciated. Thanks. Option Explicit Dim objRootDSE, strDNSDomain, adoCommand Dim adoConnection, strBase, strAttributes Dim strFilter, strQuery, adoRecordset Dim strDN, intCount, blnLast, intLowRange Dim intHighRange, intRangeStep, objField Dim objGroup, objMember, strName ' Determine DNS domain name. Set objRootDSE = GetObject("LDAP://RootDSE") 'strDNSDomain = objRootDSE.Get("DefaultNamingContext") strDNSDomain = "XXXXXXXX" ' Use ADO to search Active Directory. Set adoCommand = CreateObject("ADODB.Command") Set adoConnection = CreateObject("ADODB.Connection") adoConnection.Provider = "ADsDSOObject" adoConnection.Open = "Active Directory Provider" adoCommand.ActiveConnection = adoConnection adoCommand.Properties("Page Size") = 100 adoCommand.Properties("Timeout") = 30 adoCommand.Properties("Cache Results") = False ' Specify base of search. strBase = "<LDAP://" & strDNSDomain & ">" ' Specify the attribute values to retrieve. strAttributes = "member" ' Filter on objects of class "group" strFilter = "(&(objectClass=group)(samAccountName=*))" ' Enumerate direct group members. ' Use range limits to handle more than 1000/1500 members. ' Setup to retrieve 1000 members at a time. blnLast = False intRangeStep = 999 intLowRange = 0 IntHighRange = intLowRange + intRangeStep Do While True If (blnLast = True) Then ' If last query, retrieve remaining members. strQuery = strBase & ";" & strFilter & ";" _ & strAttributes & ";range=" & intLowRange _ & "-*;subtree" Else ' If not last query, retrieve 1000 members. strQuery = strBase & ";" & strFilter & ";" _ & strAttributes & ";range=" & intLowRange & "-" _ & intHighRange & ";subtree" End If adoCommand.CommandText = strQuery Set adoRecordset = adoCommand.Execute adoRecordset.MoveFirst intCount = 0 Do Until adoRecordset.EOF strPath = adoRecordset.Fields("ADsPath").Value Set objGroup = GetObject(strPath) For Each objField In adoRecordset.Fields If (VarType(objField) = (vbArray + vbVariant)) _ Then For Each strDN In objField.Value ' Escape any forward slash characters, "/", with the backslash ' escape character. All other characters that should be escaped are. strDN = Replace(strDN, "/", "\/") ' Check dictionary object for duplicates. 'If (objGroupList.Exists(strDN) = False) Then ' Add to dictionary object. 'objGroupList.Add strDN, True ' Bind to each group member, to find member's samAccountName Set objMember = GetObject("LDAP://" & strDN) ' Output group cn, group samaAccountName and group member's samAccountName. Wscript.Echo objMember.samAccountName intCount = intCount + 1 'End if Next End If Next adoRecordset.MoveNext Loop adoRecordset.Close ' If this is the last query, exit the Do While loop. If (blnLast = True) Then Exit Do End If ' If the previous query returned no members, then the previous ' query for the next 1000 members failed. Perform one more ' query to retrieve remaining members (less than 1000). If (intCount = 0) Then blnLast = True Else ' Setup to retrieve next 1000 members. intLowRange = intHighRange + 1 intHighRange = intLowRange + intRangeStep End If Loop

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  • mysql_query -- question about results "location"

    - by Andrew Heath
    Forgive me if this is a particularly stupid question! mysql_query($query) returns a boolean, but you can also assign it to a variable $results = mysql_query($query) and then use the other mysql_ functions to extract data. Out of curiosity, how does mysq_query($query) act as both a boolean and a data container at the same time? What's happening "under the hood" during these steps? (yes, I am a n00b..., please be kind!)

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  • Problem with Xpath PHP

    - by user294597
    Im tring to access some links through Google using xpath. The below does works fine and all the links are shown. $query = $xpath->evaluate("/html/body//a"); for ($x=0 ; $x < $query -> length; $x++) { $href=$query->item($x); $url=$href->getAttribute('href'); echo $url."<br>"; } But when i try the below xpath nothing is shown..Im sure that the xpath is correct coz its evaluated and the result is shown in xpather.. /html/body[@id='gsr']/div[@id='cnt']/div[@id='res']/div[1]/ol/li/div//cite for ($x=0 ; $x < $query -> length; $x++) { $href=$query->item($x); $url=$href->getAttribute('cite'); echo $url."<br>"; } can some one please tell me what i am doin wrong? any help will be much appreciated

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  • how do I deconstruct COUNT()?

    - by user151841
    I have a view with some joins in it. I'm doing a select from that view with COUNT(*) as one of the columns of the select. I'm surprised by the number it's returning. Note that there is no GROUP BY nor aggregate column statement in the source view that the query is drawing from. How can I take it apart to see how it arrives at this number? I have three columns in the GROUP BY clause. SELECT column1, column2, column3, COUNT(*) FROM View GROUP BY column1, column2, column3 I get a result like +---------+---------+---------+----------+ | column1 | column2 | column3 | COUNT(*) | +---------+---------+---------+----------+ | value1 | valueA | value_a | 103 | +---------+---------+---------+----------+ | value2 | valueB | value_b | 56 | +---------+---------+---------+----------+ etc. I'd like to see how it arrives at that 103, 26, etc. In other words, I want to run a query that returns 103 rows of something, so that I know that I've expressed the query properly. I'm double-checking my work. I'm not saying that I think COUNT(*) doesn't work ( I know that "SELECT is not broken" ), what I want to double-check is exactly what I'm expressing in my query, because I think I've expressed the wrong thing, which would be why I'm getting unexpected values. I need to see more what I'm actually directing MySQL to count. So should I take them one by one, and try out each value in a WHERE clause? In other words, should I do SELECT column1 FROM View WHERE column1 = 'first_grouped_value' SELECT column1 FROM View WHERE column1 = 'second_grouped_value' SELECT column2 FROM View WHERE column1 = 'first_grouped_value' SELECT column2 FROM View WHERE column1 = 'second_grouped_value' and see the row count returned matches the COUNT(*) value in the grouped results? Because of confidentiality, I won't be able to post any of the query or database structure. All I'm asking for is a general technique to see what COUNT(*) is actually counting.

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  • Listing issue, GROUP mysql

    - by SethCodes
    Here is a mock-up example of Mysql table: | ID | Country | City | ________________________________ | 1 | Sweden | Stockholm | | 2 | Sweden | Stockholm | | 3 | Sweden | Lund | | 4 | Sweden | Lund | | 5 | Germany | Berlin | | 6 | Germany | Berlin | | 7 | Germany | Hamburg | | 8 | Germany | Hamburg | Notice how both rows Country and city have repeated values inside them. Using GROUP BY country, city in my PDO query, the values will not repeat while in loop. Here is PDO for this: $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : The above code will result in an output like this (some editing in-between). GROUP BY works but the country repeats: Sweden - Stockholm Sweden - Lund Germany - Berlin Germany - Hamburg Using bootstrap collapse and above code, I separate the country from the city with a simple drop down collopase. Here is code: <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> It then looks something like this (once collapse is initiated): Sweden > Stockholm Sweden > Lund Germany >Berlin Germany >Hamburg Here is where I face the problem. The above lists the values Sweden and Germany 2 times. I want Sweden and Germany to only list one time, and the cities listed below, so the desired look is to be this: Sweden // Lists one time > Stockholm > Lund Germany // Lists one time >Berlin >Hamburg I have tried using DISTINCT, GROUP_CONTACT and other methods, yet none get my desired output (above). Suggestions? Below is my current full code in action: <? $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : ?> <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> <? endwhile ?>

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  • How would you go about tackling this problem? [SOLVED in C++]

    - by incrediman
    Intro: EDIT: See solution at the bottom of this question (c++) I have a programming contest coming up in about half a week, and I've been prepping :) I found a bunch of questions from this canadian competition, they're great practice: http://cemc.math.uwaterloo.ca/contests/computing/2009/stage2/day1.pdf I'm looking at problem B ("Dinner"). Any idea where to start? I can't really think of anything besides the naive approach (ie. trying all permutations) which would take too long to be a valid answer. Btw, the language there says c++ and pascal I think, but i don't care what language you use - I mean really all I want is a hint as to the direction I should proceed in, and perhpas a short explanation to go along with it. It feels like I'm missing something obvious... Of course extended speculation is more than welcome, but I just wanted to clarify that I'm not looking for a full solution here :) Short version of the question: You have a binary string N of length 1-100 (in the question they use H's and G's instead of one's and 0's). You must remove all of the digits from it, in the least number of steps possible. In each step you may remove any number of adjacent digits so long as they are the same. That is, in each step you can remove any number of adjacent G's, or any number of adjacent H's, but you can't remove H's and G's in one step. Example: HHHGHHGHH Solution to the example: 1. HHGGHH (remove middle Hs) 2. HHHH (remove middle Gs) 3. Done (remove Hs) -->Would return '3' as the answer. Note that there can also be a limit placed on how large adjacent groups have to be when you remove them. For example it might say '2', and then you can't remove single digits (you'd have to remove pairs or larger groups at a time). Solution I took Mark Harrison's main algorithm, and Paradigm's grouping idea and used them to create the solution below. You can try it out on the official test cases if you want. //B.cpp //include debug messages? #define DEBUG false #include <iostream> #include <stdio.h> #include <vector> using namespace std; #define FOR(i,n) for (int i=0;i<n;i++) #define FROM(i,s,n) for (int i=s;i<n;i++) #define H 'H' #define G 'G' class String{ public: int num; char type; String(){ type=H; num=0; } String(char type){ this->type=type; num=1; } }; //n is the number of bits originally in the line //k is the minimum number of people you can remove at a time //moves is the counter used to determine how many moves we've made so far int n, k, moves; int main(){ /*Input from File*/ scanf("%d %d",&n,&k); char * buffer = new char[200]; scanf("%s",buffer); /*Process input into a vector*/ //the 'line' is a vector of 'String's (essentially contigious groups of identical 'bits') vector<String> line; line.push_back(String()); FOR(i,n){ //if the last String is of the correct type, simply increment its count if (line.back().type==buffer[i]) line.back().num++; //if the last String is of the wrong type but has a 0 count, correct its type and set its count to 1 else if (line.back().num==0){ line.back().type=buffer[i]; line.back().num=1; } //otherwise this is the beginning of a new group, so create the new group at the back with the correct type, and a count of 1 else{ line.push_back(String(buffer[i])); } } /*Geedily remove groups until there are at most two groups left*/ moves=0; int I;//the position of the best group to remove int bestNum;//the size of the newly connected group the removal of group I will create while (line.size()>2){ /*START DEBUG*/ if (DEBUG){ cout<<"\n"<<moves<<"\n----\n"; FOR(i,line.size()) printf("%d %c \n",line[i].num,line[i].type); cout<<"----\n"; } /*END DEBUG*/ I=1; bestNum=-1; FROM(i,1,line.size()-1){ if (line[i-1].num+line[i+1].num>bestNum && line[i].num>=k){ bestNum=line[i-1].num+line[i+1].num; I=i; } } //remove the chosen group, thus merging the two adjacent groups line[I-1].num+=line[I+1].num; line.erase(line.begin()+I);line.erase(line.begin()+I); moves++; } /*START DEBUG*/ if (DEBUG){ cout<<"\n"<<moves<<"\n----\n"; FOR(i,line.size()) printf("%d %c \n",line[i].num,line[i].type); cout<<"----\n"; cout<<"\n\nFinal Answer: "; } /*END DEBUG*/ /*Attempt the removal of the last two groups, and output the final result*/ if (line.size()==2 && line[0].num>=k && line[1].num>=k) cout<<moves+2;//success else if (line.size()==1 && line[0].num>=k) cout<<moves+1;//success else cout<<-1;//not everyone could dine. /*START DEBUG*/ if (DEBUG){ cout<<" moves."; } /*END DEBUG*/ }

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  • Nested preference screens lose theming

    - by stealthcopter
    I have a preference screen for my application and in the manifest I have given it a theme using: android:theme="@android:style/Theme.Light.WallpaperSettings" However when I nest another preference screen inside this one such as: <?xml version="1.0" encoding="utf-8"?> <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" android:title="@string/setting_title" android:key="..."> <PreferenceCategory android:title="@string/title_themes" > <PreferenceScreen android:title="@string/title_themes_opt" > <ListPreference android:key="Setting_BG" android:title="@string/setting_bg" android:summary="@string/setting_bg_summary" android:entries="@array/bg_titles" android:defaultValue="0" android:entryValues="@array/bg_values" /> </PreferenceScreen> </PreferenceCategory> </PreferenceScreen> The nested preference screen loses the theme of the parent. How can this be prevented? Thanks in advance.

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  • scanf formatting issue

    - by da_rockwilder
    I have a log file with the following format: INFO 2011-03-09 10:26:15,270 [user] message I want to parse the log file using PHP: // assume file exists and all that $handle = fopen("log_file.txt", "r"); while ($line_data = fscanf($handle, "%s %s %s [%s] %s\n")) { var_dump($line_data); } fclose($handle); When I run this code I get: [0]=> array(5) { [0]=> string(4) "INFO" [1]=> string(10) "2011-03-09" [2]=> string(12) "10:26:15,270" [3]=> string(5) "user]" [4]=> NULL } // snip It appears the closing bracket in the format string ("%s %s %s [%s] %s") is disrupting the rest of the line from getting parsed. I checked the PHP docs for scanf (as suggested by fscanf), and I didn't see anything mentioning having to escape a left bracket. Any suggestions on how to get the 4th and 5th elements to look like "user" and "message" respectively?

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  • Conditional Batch file renaming with mysql data

    - by Paul Stevens
    Hello, I wonder if anyone knows how could I rename multiple files, all of them originally named with same structure, and add some data extracted from a mysql DB according to specifics rules. For example I have 500 files named with this vars: ID NAME ADDRESS PHONE.wav = 1234567 PAULSIMON WESTDR122 9942213456.wav Now I need to rename files taking some data from the databases for each file, and append the data from a query appended to the filename. For example add the data resulting from a query Where some conditions match, and the data to build the query is taked from original file name, as ID or NAME. i other words, lets say that I want to build a query taking ID & NAME from file 1234567 PAULSIMON WESTDR123 9942213456.wav as WHERE statements to take another value as BirthDATE and add this to new filename, so final result should be: ID NAME ADDRESS PHONE BIRTHDATE.wav I will appreciate any help on this. I need this to be done on a LINUX server.

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  • How to manually verify a user against the asp.net memberhip database

    - by Ekk
    I would like to know how I can verify a user's credential against an existing asp.net membership database. The short story is that we want provide single sign on access. So what I've done is to connect directly to the membership database and tried to run a sql query against the aspnet_Membership table: private bool CanLogin(string userName, string password) { // Check DB to see if the credential is correct try { string passwordHash = FormsAuthentication.HashPasswordForStoringInConfigFile(password, "SHA1"); string sql = string.Format("select 1 from aspnet_Users a inner join aspnet_Membership b on a.UserId = b.UserId and a.applicationid = b.applicationid where a.username = '{0}' and b.password='{1}'", userName.ToLowerInvariant(), passwordHash); using (SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["LocalSqlServer"].ConnectionString)) using (SqlCommand sqlCmd = new SqlCommand(sql, sqlConn)) { sqlConn.Open(); int count = sqlCmd.ExecuteNonQuery(); sqlConn.Close(); return count == 1; } } catch (Exception ex) { return false; } } The problem is the password value, does anyone know how the password it is hashed?

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  • Using charAt in java

    - by ThuL?nå F?rñ?nDö
    This is my assignment: Write a program where the user enters a string, and the program echoes it to the monitor with one character per line: C:\>java LinePerChar Enter a string: Octopus O c t o p u s I have tried, but I'm getting some compilation errors. Here's my code: import java.util.*; class CharactorEcho{ public static void main(String args []){ Scanner sc = new Scanner(System.in); System.out.println("Enter a string :"); try { String inputString = sc.nextLine(); for(int i=0; i < sc.length(); i++) { char c = inputString.charAt(i); System.out.println("" + c); } } catch(IOException e) { } } }

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  • how can user_DEPENDENCIES read from the procedure

    - by Moudiz
    If I run this query : SELECT DISTINCT U.REFERENCED_NAME, U.REFERENCED_TYPE FROM USER_DEPENDENCIES U where U.name IN('P_CREATE_T') It will give me : U.REFERENCED_NAME | U.REFERENCED_TYPE random_name_table | table If I drop this table random_name_table : drop table random_name_table and I run the dependecie query It will give me this: U.REFERENCED_NAME | U.REFERENCED_TYPE BIN$6WfJh8MWWGngQ3ATqMDOpQ==$0 | table I know the result is related to recycle bin, But what I am asking is there a way that shows the table even if its droped ? I mean shouldnt the depency query read from the procedure and not from the database ? If not is there a query that reads from the procedure and not from database ? Edit ok I will make it clear : my question USER_DEPENDENCIES read from the procedure or the database ? My second question does the recycle bin always shows ? I mean is there times where the result of the recylebin disapear ?

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  • PHP, MySQL prepared statements - can you use results of execute more than once by calling data_seek(

    - by Carvell Fenton
    Hello, I have a case where I want to use the results of a prepared statement more than once in a nested loop. The outer loop processes the results of another query, and the inner loop is the results of the prepared statement query. So the code would be something like this (just "pseudoish" to demonstrate the concept): // not showing the outer query, it is just a basic SELECT, not prepared statement // we'll call it $outer_query $obj_array = array(); // going to save objects in this $ids = array(18,19,20); // just example id numbers $query = "SELECT field1, field2 FROM table1 WHERE id=?"; $stmt = $db->prepare($query); foreach ($ids as $id) { $stmt->bind_param("i", $id); $stmt->execute(); $stmt->bind_result($var1, $var2); $stmt->store_result(); // I think I need this for data_seek while ($q1 = $outer_query->fetch_object()) { while ($stmt->fetch()) { if ($q1->field1 == $var1) { // looking for a match $obj = new stdClass(); $obj->var1 = $var1; $obj->var2 = $var2; $obj_array[] = $obj; $stmt->data_seek(0); // reset for outer loop break; // found match, so leave inner } } } } The problem I seem to be experiencing is that the values are not getting bound in the variables as I would expect after the first time I use fetch in the inner loop. Specifically, in one example I ran with 3 ids for the foreach, the first id was processed correctly, the second was processed incorrectly (matches were not found in the inner loop even though they existed), and then the third was processed correctly. Is there something wrong with the prepared statment function calls in the sequence I am doing above, or is this an invalid way to use the results of the prepared statement? Thanks.

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  • highlight multiple keywords in search

    - by fusion
    i'm using this code to highlight search keywords: function highlightWords($string, $word) { $string = str_replace($word, "<span class='highlight'>".$word."</span>", $string); /*** return the highlighted string ***/ return $string; } .... $cQuote = highlightWords(htmlspecialchars($row['cQuotes']), $search_result); however, this highlights only one keyword. if the user enters more than one keyword, it will narrow down the search but no word is highlighted. how can i highlight more than one word?

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  • SQL Server uncorrelated subquery very slow

    - by brianberns
    I have a simple, uncorrelated subquery that performs very poorly on SQL Server. I'm not very experienced at reading execution plans, but it looks like the inner query is being executed once for every row in the outer query, even though the results are the same each time. What can I do to tell SQL Server to execute the inner query only once? The query looks like this: select * from Record record0_ where record0_.RecordTypeFK='c2a0ffa5-d23b-11db-9ea3-000e7f30d6a2' and ( record0_.EntityFK in ( select record1_.EntityFK from Record record1_ join RecordTextValue textvalues2_ on record1_.PK=textvalues2_.RecordFK and textvalues2_.FieldFK = '0d323c22-0ec2-11e0-a148-0018f3dde540' and (textvalues2_.Value like 'O%' escape '~') ) )

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  • Why does SQLAlchemy with psycopg2 use_native_unicode have poor performance?

    - by Bob Dover
    I'm having a difficult time figuring out why a simple SELECT query is taking such a long time with sqlalchemy using raw SQL (I'm getting 14600 rows/sec, but when running the same query through psycopg2 without sqlalchemy, I'm getting 38421 rows/sec). After some poking around, I realized that toggling sqlalchemy's use_native_unicode parameter in the create_engine call actually makes a huge difference. This query takes 0.5secs to retrieve 7300 rows: from sqlalchemy import create_engine engine = create_engine("postgresql+psycopg2://localhost...", use_native_unicode=True) r = engine.execute("SELECT * FROM logtable") fetched_results = r.fetchall() This query takes 0.19secs to retrieve the same 7300 rows: engine = create_engine("postgresql+psycopg2://localhost...", use_native_unicode=False) r = engine.execute("SELECT * FROM logtable") fetched_results = r.fetchall() The only difference between the 2 queries is use_native_unicode. But sqlalchemy's own docs state that it is better to keep use_native_unicode=True (http://docs.sqlalchemy.org/en/latest/dialects/postgresql.html). Does anyone know why use_native_unicode is making such a big performance difference? And what are the ramifications of turning off use_native_unicode?

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  • How to detect column conflicts with Hibernate?

    - by Slim
    So let's say I have an ArrayList full of Products that need to be committed to the database via Hibernate. There are already a large number of Products in the database. Each product has an ID. Note this is NOT the PK that is autogenerated by Hibernate. My questions is: what is the best way to detect conflicts with this ID? I am looking for a relatively efficient method of obtaining, from the the database, a List of Products that share an ID with any of the Products in my ArrayList. This is all in a single table called Products and the ID attribute is in column ProductID. The way I've done it is grabbing a list of all Products in the database, and compared each one with each entry in my ArrayList - but that is seriously inefficient and I don't think it would work well with a larger database. How should it be done? Thanks. I say "relatively" efficient because efficiency is not the primary concern, but it shouldn't take noticeably long to test against a table of ~1000-5000 rows. Help? EDIT* I'm very new to hibernate and below is the best I've come up with. How does this look? for(long id : idList){ //idList just holds the IDs of each Product in my ArrayList Query query = session.createQuery("select product from Product product where product.id = :id"); query.setLong("id", id); for(int i = 0; i < query.list().size(); i++){ listOfConflictingProducts.add((Product) query.list().get(i)); } }

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  • A column ID occurred more than once in the specification

    - by Puzzle84
    Recently i've picked up my EF 4.1 / MVC 3 project again and started building in actual frontend capabilities. Now i'm developing a "simple" message system but upon going to that page i get the error as stated in the title EDIT It creates the database just not the models. Stack trace: [NullReferenceException: Object reference not set to an instance of an object.] ASP._Page_Views_Inbox_Index_cshtml.Execute() in c:\Development\MVC\DOCCL\Views\Inbox\Index.cshtml:18 System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +197 System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +81 System.Web.WebPages.StartPage.RunPage() +17 System.Web.WebPages.StartPage.ExecutePageHierarchy() +62 System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +76 System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance) +222 System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer) +115 System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +295 System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) +13 System.Web.Mvc.<c_DisplayClass1c.b_19() +23 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func1 continuation) +242 System.Web.Mvc.<>c__DisplayClass1e.<InvokeActionResultWithFilters>b__1b() +21 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList1 filters, ActionResult actionResult) +177 System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +324 System.Web.Mvc.Controller.ExecuteCore() +106 System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +91 System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +10 System.Web.Mvc.<c_DisplayClassb.b_5() +34 System.Web.Mvc.Async.<c_DisplayClass1.b_0() +19 System.Web.Mvc.Async.<c_DisplayClass81.<BeginSynchronous>b__7(IAsyncResult _) +10 System.Web.Mvc.Async.WrappedAsyncResult1.End() +62 System.Web.Mvc.<c_DisplayClasse.b_d() +48 System.Web.Mvc.SecurityUtil.b_0(Action f) +7 System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Action action) +22 System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +60 System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9478661 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +178 InnerException : {"A column ID occurred more than once in the specification."} The recently added code is. Controller: // // GET: /Inbox/Index/5/1 public ActionResult Index(int? Id, int Page = 1) { try { const int pageSize = 10; var messages = from m in horseTracker.Messages where m.ReceiverId.Equals(Id) select m; var paginatedMessages = new PaginatedList<Message>(messages, Page, pageSize); return View(paginatedMessages); } catch (Exception ex) { } return View(); } Models public class Message { [Key] public int Id { get; set; } [Required(ErrorMessage = "Subject is required")] [Display(Name = "Subject")] public string Subject { get; set; } [Required(ErrorMessage = "Message is required")] [Display(Name = "Message")] public string Content { get; set; } [Required] [Display(Name = "Date")] public DateTime Created { get; set; } public Boolean Read { get; set; } [Required(ErrorMessage = "Can't create a message without a user")] public int SenderId { get; set; } public virtual User Sender { get; set; } [Required(ErrorMessage = "Please pick a recipient")] public int ReceiverId { get; set; } public virtual User Receiver { get; set; } } public class User { [Key] public int Id { get; set; } [Required] [Display(Name = "Username")] public string UserName { get; set; } [Required] [Display(Name = "First Name")] public string FirstName { get; set; } [Required] [Display(Name = "Last Name")] public string LastName { get; set; } [Required] [Display(Name = "E-Mail")] public string Email { get; set; } [Required] [Display(Name = "Password")] public string Password { get; set; } [Required] [Display(Name = "Country")] public string Country { get; set; } public string EMail { get; set; } //Races public virtual ICollection<Message> Messages { get; set; } } modelBuilder.Entity<User>() .HasMany(u => u.Messages) .WithRequired(m => m.Receiver) .HasForeignKey(m => m.ReceiverId) .WillCascadeOnDelete(false); Anyone have a clue on why i might be getting that error? Before i added these classes it was working fine.

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  • Zend_Table_Db and Zend_Paginator num rows

    - by Uffo
    I have the following query: $this->select() ->where("`name` LIKE ?",'%'.mysql_escape_string($name).'%') Now I have the Zend_Paginator code: $paginator = new Zend_Paginator( // $d is an instance of Zend_Db_Select new Zend_Paginator_Adapter_DbSelect($d) ); $paginator->getAdapter()->setRowCount(200); $paginator->setItemCountPerPage(15) ->setPageRange(10) ->setCurrentPageNumber($pag); $this->view->data = $paginator; As you see I'm passing the data to the view using $this->view->data = $paginator Before I didn't had $paginator->getAdapter()->setRowCount(200);I could determinate If I have any data or not, what I mean with data, if the query has some results, so If the query has some results I show the to the user, if not, I need to show them a message(No results!) But in this moment I don't know how can I determinate this, since count($paginator) doesn't work anymore because of $paginator->getAdapter()->setRowCount(200);and I'm using this because it taks about 7 sec for Zend_Paginator to count the page numbers. So how can I find If my query has any results?

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  • Is it a bad idea to use the new Dynamic Keyword as a replacement switch statement?

    - by WeNeedAnswers
    I like the new Dynamic keyword and read that it can be used as a replacement visitor pattern. It makes the code more declarative which I prefer. Is it a good idea though to replace all instances of switch on 'Type' with a class that implements dynamic dispatch. class VistorTest { public string DynamicVisit(object obj) { return Visit((dynamic)obj); } private string Visit(string str) { return "a string was called with value " + str; } private string Visit(int value) { return "an int was called with value " + value; } }

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