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  • Another C datatypes question

    - by b-gen-jack-o-neill
    Hello. Well, I completely get the most basic datatypes of C, like short, int, long, float, to be exact, all numerical types.These types are needed to be known perform right operations with right numbers. For example to use FPU to add two float numbers. So the compiler must know what the type is. But, when it comes to characters I am little bit off. I know that basic C datatype char is there for ASCII characters coding. But what I don´t know is, why you even need another datatype for characters. Why could not you just use 1 byte integer value to store ASCII character. If you call printf, you apecify the datatype in the call, so you could say to printf that the integer represents ASCII character. I dont know how cout resolves datatype, but I guess you could just specify it somehow. Another thing is, when you want to use Unicode, you must use datatype wchar. But, what if I would like to use some another, for example ISO, or Windows coding instead of UTF? Becouse wchar codes characters as UTF-16 or UTF-32 (I read its compiler specific). And, what if I would want to use for example some imaginary new 8 byte text coding? What datatype should I use for it? I am actually pretty confused of this, becouse I always expected that if I want to use UTF-32 instead of ASCII, I just tell compiler "get UTF-32 value of the character I typed and save it into 4 char field." I thought that text coding is to be dealt with by the end, print function for example. That I just need to specify the coding for the compiler to use, since Windows doesent use ASCII in win32 apps, I guess C compiler must convert the char I typed to ASCII from whatever the type is that windows sends to the C editor. And the last thing is, what if I want to use for example 25 Byte integer for some high math operations? C has no specify-yourself datatype. Yes, I know that this would be difficult since all the math operations would need to be changed, becouse CPU can not add 25 Bytes numbers together. But is there a way to do it? Or is there some math library for it? What if I want to compute Pi to 1000000000000000 digits? :) I know my question is pretty long, but I just wanted to explain my thoughts the best I can in English, since its not my native language it is difficult. And I believe there is simple answer to my question(s), something I missed that explains everything. I read lot about text coding, C tutorials, but nothing about his. Thank you for your time.

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  • Octave datatypes - float & double

    - by mush
    I'm writing a framework for writing HDF files with JAVA (Using some existing framework). I need to keep compatibility with octave. That is, octave should be able to read the files my framework writes and vice versa. My question is, does Octave have two data types - float and double or it uses only double? thanks

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  • functional-style datatypes in Python

    - by Danny Roberts
    For anyone who's spent some time with sml, ocaml, haskell, etc. when you go back to using C, Python, Java, etc. you start to notice things you never knew were missing. I'm doing some stuff in Python and I realized what I really want is a functional-style datatype like (for example) datatype phoneme = Vowel of string | Consonant of voice * place * manner datatype voice = Voiced | Voiceless datatype place = Labial | Dental | Retroflex | Palatal | Velar | Glottal datatype manner = Stop | Affricate | Fricative | Nasal | Lateral type syllable = phoneme list Does anyone have a particular way that they like to simulate this in Python?

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  • Range of int and long datatypes

    - by n00b8688
    I learned the range of int and long on 32 bit windows is: signed int: -32767 to 32767 signed long: -2147483647 to 2147483647 why does the int has same range as long type as mentioned here? http://msdn.microsoft.com/en-us/library/s3f49ktz%28VS.80%29.aspx

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  • Datatypes for physics

    - by Juan Manuel Formoso
    Hi, I'm currently designing a program that will involve some physics (nothing too fancy, a few balls crashing to each other) What's the most exact datatype I can use to represent position (without a feeling of discrete jumps) in c#? Also, what's the smallest ammount of time I can get between t and t+1? One tick? EDIT: Clarifying: What is the smallest unit of time in C#? [TimeSpan].Tick?

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  • Sniffing out SQL Code Smells: Inconsistent use of Symbolic names and Datatypes

    - by Phil Factor
    It is an awkward feeling. You’ve just delivered a database application that seems to be working fine in production, and you just run a few checks on it. You discover that there is a potential bug that, out of sheer good chance, hasn’t kicked in to produce an error; but it lurks, like a smoking bomb. Worse, maybe you find that the bug has started its evil work of corrupting the data, but in ways that nobody has, so far detected. You investigate, and find the damage. You are somehow going to have to repair it. Yes, it still very occasionally happens to me. It is not a nice feeling, and I do anything I can to prevent it happening. That’s why I’m interested in SQL code smells. SQL Code Smells aren’t necessarily bad practices, but just show you where to focus your attention when checking an application. Sometimes with databases the bugs can be subtle. SQL is rather like HTML: the language does its best to try to carry out your wishes, rather than to be picky about your bugs. Most of the time, this is a great benefit, but not always. One particular place where this can be detrimental is where you have implicit conversion between different data types. Most of the time it is completely harmless but we’re  concerned about the occasional time it isn’t. Let’s give an example: String truncation. Let’s give another even more frightening one, rounding errors on assignment to a number of different precision. Each requires a blog-post to explain in detail and I’m not now going to try. Just remember that it is not always a good idea to assign data to variables, parameters or even columns when they aren’t the same datatype, especially if you are relying on implicit conversion to work its magic.For details of the problem and the consequences, see here:  SR0014: Data loss might occur when casting from {Type1} to {Type2} . For any experienced Database Developer, this is a more frightening read than a Vampire Story. This is why one of the SQL Code Smells that makes me edgy, in my own or other peoples’ code, is to see parameters, variables and columns that have the same names and different datatypes. Whereas quite a lot of this is perfectly normal and natural, you need to check in case one of two things have gone wrong. Either sloppy naming, or mixed datatypes. Sure it is hard to remember whether you decided that the length of a log entry was 80 or 100 characters long, or the precision of a number. That is why a little check like this I’m going to show you is excellent for tidying up your code before you check it back into source Control! 1/ Checking Parameters only If you were just going to check parameters, you might just do this. It simply groups all the parameters, either input or output, of all the routines (e.g. stored procedures or functions) by their name and checks to see, in the HAVING clause, whether their data types are all the same. If not, it lists all the examples and their origin (the routine) Even this little check can occasionally be scarily revealing. ;WITH userParameter AS  ( SELECT   c.NAME AS ParameterName,  OBJECT_SCHEMA_NAME(c.object_ID) + '.' + OBJECT_NAME(c.object_ID) AS ObjectName,  t.name + ' '     + CASE     --we may have to put in the length            WHEN t.name IN ('char', 'varchar', 'nchar', 'nvarchar')             THEN '('               + CASE WHEN c.max_length = -1 THEN 'MAX'                ELSE CONVERT(VARCHAR(4),                    CASE WHEN t.name IN ('nchar', 'nvarchar')                      THEN c.max_length / 2 ELSE c.max_length                    END)                END + ')'         WHEN t.name IN ('decimal', 'numeric')             THEN '(' + CONVERT(VARCHAR(4), c.precision)                   + ',' + CONVERT(VARCHAR(4), c.Scale) + ')'         ELSE ''      END  --we've done with putting in the length      + CASE WHEN XML_collection_ID <> 0         THEN --deal with object schema names             '(' + CASE WHEN is_XML_Document = 1                    THEN 'DOCUMENT '                    ELSE 'CONTENT '                   END              + COALESCE(               (SELECT QUOTENAME(ss.name) + '.' + QUOTENAME(sc.name)                FROM sys.xml_schema_collections sc                INNER JOIN Sys.Schemas ss ON sc.schema_ID = ss.schema_ID                WHERE sc.xml_collection_ID = c.XML_collection_ID),'NULL') + ')'          ELSE ''         END        AS [DataType]  FROM sys.parameters c  INNER JOIN sys.types t ON c.user_Type_ID = t.user_Type_ID  WHERE OBJECT_SCHEMA_NAME(c.object_ID) <> 'sys'   AND parameter_id>0)SELECT CONVERT(CHAR(80),objectName+'.'+ParameterName),DataType FROM UserParameterWHERE ParameterName IN   (SELECT ParameterName FROM UserParameter    GROUP BY ParameterName    HAVING MIN(Datatype)<>MAX(DataType))ORDER BY ParameterName   so, in a very small example here, we have a @ClosingDelimiter variable that is only CHAR(1) when, by the looks of it, it should be up to ten characters long, or even worse, a function that should be a char(1) and seems to let in a string of ten characters. Worth investigating. Then we have a @Comment variable that can't decide whether it is a VARCHAR(2000) or a VARCHAR(MAX) 2/ Columns and Parameters Actually, once we’ve cleared up the mess we’ve made of our parameter-naming in the database we’re inspecting, we’re going to be more interested in listing both columns and parameters. We can do this by modifying the routine to list columns as well as parameters. Because of the slight complexity of creating the string version of the datatypes, we will create a fake table of both columns and parameters so that they can both be processed the same way. After all, we want the datatypes to match Unfortunately, parameters do not expose all the attributes we are interested in, such as whether they are nullable (oh yes, subtle bugs happen if this isn’t consistent for a datatype). We’ll have to leave them out for this check. Voila! A slight modification of the first routine ;WITH userObject AS  ( SELECT   Name AS DataName,--the actual name of the parameter or column ('@' removed)  --and the qualified object name of the routine  OBJECT_SCHEMA_NAME(ObjectID) + '.' + OBJECT_NAME(ObjectID) AS ObjectName,  --now the harder bit: the definition of the datatype.  TypeName + ' '     + CASE     --we may have to put in the length. e.g. CHAR (10)           WHEN TypeName IN ('char', 'varchar', 'nchar', 'nvarchar')             THEN '('               + CASE WHEN MaxLength = -1 THEN 'MAX'                ELSE CONVERT(VARCHAR(4),                    CASE WHEN TypeName IN ('nchar', 'nvarchar')                      THEN MaxLength / 2 ELSE MaxLength                    END)                END + ')'         WHEN TypeName IN ('decimal', 'numeric')--a BCD number!             THEN '(' + CONVERT(VARCHAR(4), Precision)                   + ',' + CONVERT(VARCHAR(4), Scale) + ')'         ELSE ''      END  --we've done with putting in the length      + CASE WHEN XML_collection_ID <> 0 --tush tush. XML         THEN --deal with object schema names             '(' + CASE WHEN is_XML_Document = 1                    THEN 'DOCUMENT '                    ELSE 'CONTENT '                   END              + COALESCE(               (SELECT TOP 1 QUOTENAME(ss.name) + '.' + QUOTENAME(sc.Name)                FROM sys.xml_schema_collections sc                INNER JOIN Sys.Schemas ss ON sc.schema_ID = ss.schema_ID                WHERE sc.xml_collection_ID = XML_collection_ID),'NULL') + ')'          ELSE ''         END        AS [DataType],       DataObjectType  FROM   (Select t.name AS TypeName, REPLACE(c.name,'@','') AS Name,          c.max_length AS MaxLength, c.precision AS [Precision],           c.scale AS [Scale], c.[Object_id] AS ObjectID, XML_collection_ID,          is_XML_Document,'P' AS DataobjectType  FROM sys.parameters c  INNER JOIN sys.types t ON c.user_Type_ID = t.user_Type_ID  AND parameter_id>0  UNION all  Select t.name AS TypeName, c.name AS Name, c.max_length AS MaxLength,          c.precision AS [Precision], c.scale AS [Scale],          c.[Object_id] AS ObjectID, XML_collection_ID,is_XML_Document,          'C' AS DataobjectType            FROM sys.columns c  INNER JOIN sys.types t ON c.user_Type_ID = t.user_Type_ID   WHERE OBJECT_SCHEMA_NAME(c.object_ID) <> 'sys'  )f)SELECT CONVERT(CHAR(80),objectName+'.'   + CASE WHEN DataobjectType ='P' THEN '@' ELSE '' END + DataName),DataType FROM UserObjectWHERE DataName IN   (SELECT DataName FROM UserObject   GROUP BY DataName    HAVING MIN(Datatype)<>MAX(DataType))ORDER BY DataName     Hmm. I can tell you I found quite a few minor issues with the various tabases I tested this on, and found some potential bugs that really leap out at you from the results. Here is the start of the result for AdventureWorks. Yes, AccountNumber is, for some reason, a Varchar(10) in the Customer table. Hmm. odd. Why is a city fifty characters long in that view?  The idea of the description of a colour being 256 characters long seems over-ambitious. Go down the list and you'll spot other mistakes. There are no bugs, but just mess. We started out with a listing to examine parameters, then we mixed parameters and columns. Our last listing is for a slightly more in-depth look at table columns. You’ll notice that we’ve delibarately removed the indication of whether a column is persisted, or is an identity column because that gives us false positives for our code smells. If you just want to browse your metadata for other reasons (and it can quite help in some circumstances) then uncomment them! ;WITH userColumns AS  ( SELECT   c.NAME AS columnName,  OBJECT_SCHEMA_NAME(c.object_ID) + '.' + OBJECT_NAME(c.object_ID) AS ObjectName,  REPLACE(t.name + ' '   + CASE WHEN is_computed = 1 THEN ' AS ' + --do DDL for a computed column          (SELECT definition FROM sys.computed_columns cc           WHERE cc.object_id = c.object_id AND cc.column_ID = c.column_ID)     --we may have to put in the length            WHEN t.Name IN ('char', 'varchar', 'nchar', 'nvarchar')             THEN '('               + CASE WHEN c.Max_Length = -1 THEN 'MAX'                ELSE CONVERT(VARCHAR(4),                    CASE WHEN t.Name IN ('nchar', 'nvarchar')                      THEN c.Max_Length / 2 ELSE c.Max_Length                    END)                END + ')'       WHEN t.name IN ('decimal', 'numeric')       THEN '(' + CONVERT(VARCHAR(4), c.precision) + ',' + CONVERT(VARCHAR(4), c.Scale) + ')'       ELSE ''      END + CASE WHEN c.is_rowguidcol = 1          THEN ' ROWGUIDCOL'          ELSE ''         END + CASE WHEN XML_collection_ID <> 0            THEN --deal with object schema names             '(' + CASE WHEN is_XML_Document = 1                THEN 'DOCUMENT '                ELSE 'CONTENT '               END + COALESCE((SELECT                QUOTENAME(ss.name) + '.' + QUOTENAME(sc.name)                FROM                sys.xml_schema_collections sc                INNER JOIN Sys.Schemas ss ON sc.schema_ID = ss.schema_ID                WHERE                sc.xml_collection_ID = c.XML_collection_ID),                'NULL') + ')'            ELSE ''           END + CASE WHEN is_identity = 1             THEN CASE WHEN OBJECTPROPERTY(object_id,                'IsUserTable') = 1 AND COLUMNPROPERTY(object_id,                c.name,                'IsIDNotForRepl') = 0 AND OBJECTPROPERTY(object_id,                'IsMSShipped') = 0                THEN ''                ELSE ' NOT FOR REPLICATION '               END             ELSE ''            END + CASE WHEN c.is_nullable = 0               THEN ' NOT NULL'               ELSE ' NULL'              END + CASE                WHEN c.default_object_id <> 0                THEN ' DEFAULT ' + object_Definition(c.default_object_id)                ELSE ''               END + CASE                WHEN c.collation_name IS NULL                THEN ''                WHEN c.collation_name <> (SELECT                collation_name                FROM                sys.databases                WHERE                name = DB_NAME()) COLLATE Latin1_General_CI_AS                THEN COALESCE(' COLLATE ' + c.collation_name,                '')                ELSE ''                END,'  ',' ') AS [DataType]FROM sys.columns c  INNER JOIN sys.types t ON c.user_Type_ID = t.user_Type_ID  WHERE OBJECT_SCHEMA_NAME(c.object_ID) <> 'sys')SELECT CONVERT(CHAR(80),objectName+'.'+columnName),DataType FROM UserColumnsWHERE columnName IN (SELECT columnName FROM UserColumns  GROUP BY columnName  HAVING MIN(Datatype)<>MAX(DataType))ORDER BY columnName If you take a look down the results against Adventureworks, you'll see once again that there are things to investigate, mostly, in the illustration, discrepancies between null and non-null datatypes So I here you ask, what about temporary variables within routines? If ever there was a source of elusive bugs, you'll find it there. Sadly, these temporary variables are not stored in the metadata so we'll have to find a more subtle way of flushing these out, and that will, I'm afraid, have to wait!

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  • Some datatypes doesn't honor localization

    - by Peter Larsson
    This bug has haunted me for a while, until today when I decided to not accept it anymore. So I filed a bug over at connect.microsoft.com, https://connect.microsoft.com/SQLServer/feedback/details/636074/some-datatypes-doesnt-honor-localization, and if you feel the way I do, please vote for this bug to be fixed. Here is a very simple repro of the problem DECLARE  @Sample TABLE          (              a DECIMAL(38, 19),              b FLOAT          ) INSERT   @Sample          (              a,              b          ) VALUES   (1E / 7E, 1E / 7E) SELECT   * FROM     @Sample Here is the actual output.                                       a                      b --------------------------------------- ----------------------                   0.1428571428571428400      0,142857142857143   I think that both columns should have the same decimal separator, don't you? //Peter

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  • Why can I query with an int but not a string here? PHP MySQL Datatypes

    - by CT
    I am working on an Asset Database problem. I receive $id from $_GET["id"]; I then query the database and display the results. This works if my id is an integer like "93650" but if it has other characters like "wci1001", it displays this MySQL error: Unknown column 'text' in 'where clause' All fields in tables are of type: VARCHAR(50) What would I need to do to be able to use this query to search by id that includes other characters? Thank you. <?php <?php /* * ASSET DB FUNCTIONS SCRIPT * */ # connect to database function ConnectDB(){ mysql_connect("localhost", "asset_db", "asset_db") or die(mysql_error()); mysql_select_db("asset_db") or die(mysql_error()); } # find asset type returns $type function GetAssetType($id){ $sql = "SELECT asset.type From asset WHERE asset.id = $id"; $result = mysql_query($sql) or die(mysql_error()); $row = mysql_fetch_assoc($result); $type = $row['type']; return $type; } # query server returns $result (sql query array) function QueryServer($id){ $sql = " SELECT asset.id ,asset.company ,asset.location ,asset.purchaseDate ,asset.purchaseOrder ,asset.value ,asset.type ,asset.notes ,server.manufacturer ,server.model ,server.serialNumber ,server.esc ,server.warranty ,server.user ,server.prevUser ,server.cpu ,server.memory ,server.hardDrive FROM asset LEFT JOIN server ON server.id = asset.id WHERE asset.id = $id "; $result = mysql_query($sql); return $result; } # get server data returns $serverArray function GetServerData($result){ while($row = mysql_fetch_assoc($result)) { $id = $row['id']; $company = $row['company']; $location = $row['location']; $purchaseDate = $row['purchaseDate']; $purchaseOrder = $row['purchaseOrder']; $value = $row['value']; $type = $row['type']; $notes = $row['notes']; $manufacturer = $row['manufacturer']; $model = $row['model']; $serialNumber = $row['serialNumber']; $esc = $row['esc']; $warranty = $row['warranty']; $user = $row['user']; $prevUser = $row['prevUser']; $cpu = $row['cpu']; $memory = $row['memory']; $hardDrive = $row['hardDrive']; $serverArray = array($id, $company, $location, $purchaseDate, $purchaseOrder, $value, $type, $notes, $manufacturer, $model, $serialNumber, $esc, $warranty, $user, $prevUser, $cpu, $memory, $hardDrive); } return $serverArray; } # print server table function PrintServerTable($serverArray){ $id = $serverArray[0]; $company = $serverArray[1]; $location = $serverArray[2]; $purchaseDate = $serverArray[3]; $purchaseOrder = $serverArray[4]; $value = $serverArray[5]; $type = $serverArray[6]; $notes = $serverArray[7]; $manufacturer = $serverArray[8]; $model = $serverArray[9]; $serialNumber = $serverArray[10]; $esc = $serverArray[11]; $warranty = $serverArray[12]; $user = $serverArray[13]; $prevUser = $serverArray[14]; $cpu = $serverArray[15]; $memory = $serverArray[16]; $hardDrive = $serverArray[17]; echo "<table width=\"100%\" border=\"0\"><tr><td style=\"vertical-align:top\"><table width=\"100%\" border=\"0\"><tr><td colspan=\"2\"><h2>General Info</h2></td></tr><tr id=\"hightlight\"><td>Asset ID:</td><td>"; echo $id; echo "</td></tr><tr><td>Company:</td><td>"; echo $company; echo "</td></tr><tr id=\"hightlight\"><td>Location:</td><td>"; echo $location; echo "</td></tr><tr><td>Purchase Date:</td><td>"; echo $purchaseDate; echo "</td></tr><tr id=\"hightlight\"><td>Purchase Order #:</td><td>"; echo $purchaseOrder; echo "</td></tr><tr><td>Value:</td><td>"; echo $value; echo "</td></tr><tr id=\"hightlight\"><td>Type:</td><td>"; echo $type; echo "</td></tr><tr><td>Notes:</td><td>"; echo $notes; echo "</td></tr></table></td><td style=\"vertical-align:top\"><table width=\"100%\" border=\"0\"><tr><td colspan=\"2\"><h2>Server Info</h2></td></tr><tr id=\"hightlight\"><td>Manufacturer:</td><td>"; echo $manufacturer; echo "</td></tr><tr><td>Model:</td><td>"; echo $model; echo "</td></tr><tr id=\"hightlight\"><td>Serial Number:</td><td>"; echo $serialNumber; echo "</td></tr><tr><td>ESC:</td><td>"; echo $esc; echo "</td></tr><tr id=\"hightlight\"><td>Warranty:</td><td>"; echo $warranty; echo "</td></tr><tr><td colspan=\"2\">&nbsp;</td></tr><tr><td colspan=\"2\"><h2>User Info</h2></td></tr><tr id=\"hightlight\"><td>User:</td><td>"; echo $user; echo "</td></tr><tr><td>Previous User:</td><td>"; echo $prevUser; echo "</td></tr></table></td><td style=\"vertical-align:top\"><table width=\"100%\" border=\"0\"><tr><td colspan=\"2\"><h2>Specs</h2></td></tr><tr id=\"hightlight\"><td>CPU:</td><td>"; echo $cpu; echo "</td></tr><tr><td>Memory:</td><td>"; echo $memory; echo "</td></tr><tr id=\"hightlight\"><td>Hard Drive:</td><td>"; echo $hardDrive; echo "</td></tr><tr><td colspan=\"2\">&nbsp;</td></tr><tr><td colspan=\"2\">&nbsp;</td></tr><tr><td colspan=\"2\"><h2>Options</h2></td></tr><tr><td colspan=\"2\"><a href=\"#\">Edit Asset</a></td></tr><tr><td colspan=\"2\"><a href=\"#\">Delete Asset</a></td></tr></table></td></tr></table>"; } ?> __ /* * View Asset * */ # include functions script include "functions.php"; $id = $_GET["id"]; if (empty($id)):$id="000"; endif; ConnectDB(); $type = GetAssetType($id); ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="style.css" /> <title>Wagman IT Asset</title> </head> <body> <div id="page"> <div id="header"> <img src="images/logo.png" /> </div> </div> <div id="content"> <div id="container"> <div id="main"> <div id="menu"> <ul> <table width="100%" border="0"> <tr> <td width="15%"></td> <td width="30%%"><li><a href="index.php">Search Assets</a></li></td> <td width="30%"><li><a href="addAsset.php">Add Asset</a></li></td> <td width="25%"></td> </tr> </table> </ul> </div> <div id="text"> <ul> <li> <h1>View Asset</h1> </li> </ul> <?php if (empty($type)):echo "<ul><li><h2>Asset ID does not match any database entries.</h2></li></ul>"; else: switch ($type){ case "Server": $result = QueryServer($id); $ServerArray = GetServerData($result); PrintServerTable($ServerArray); break; case "Desktop"; break; case "Laptop"; break; } endif; ?> </div> </div> </div> <div class="clear"></div> <div id="footer" align="center"> <p>&nbsp;</p> </div> </div> <div id="tagline"> Wagman Construction - Bridging Generations since 1902 </div> </body> </html>

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  • Retrieving datatypes from underlying database

    - by H4mm3rHead
    Hi, Im making an application that displays information about an underlying database. The database can be anything, but is typically either Oracle, MSSQL or MySQL. I am trying to extract the datatype but cannot seem to get this right. I have a DbConnection because i dont know whether I need a OleDbConnection or an OdbcConnection. On this connection I make a GetSchema("Columns", "mytablename") query and gets the result back. It seems though that there are some inconsistencies with my datatypes or the query returns different datatypes for the different databases. For instance, in my MSSQL database I query and get an integer back (which seems to be the OleDbType) which I map to a datatype. My varchars is now of type char - no length - and this confuses me a bit. I guess my main question is something like: Is there any way of making a uniform way of extracting datatypes across providers and having an "accurate" representation of the datatype?

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  • What really happens when I use varchar(10) in the sqlite command-line shell?

    - by romandas
    I'm messing around with SQLite for the first time by working through some of the SQLite documentation. In particular, I'm using Command Line Shell For SQLite and the SoupToNuts SQLite Tutorial on Sourceforge. According to the SQLite datatype documentation, there are only 5 datatypes in SQLite. However, in the two tutorial documents above, I see where the authors use commands such as create table tbl1(one varchar(10), two smallint); or create table t1 (t1key INTEGER PRIMARY KEY,data TEXT,num double,timeEnter DATE); which contain datatypes that aren't listed by SQLite, yet these commands work just fine. Additionally, when I ran .dump to see the SQL statements, these datatype specifications are preserved. So, what gives? Does SQLite keep a reference for any datatype specified in the SQL yet converts it behind the scenes to one of its 5 datatypes? Or is there something else I'm missing?

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  • Anybody got a C# function that maps the SQL datatype of a column to its CLR equivalent?

    - by Chris McCall
    I'm sitting down to write a massive switch() statement to turn SQL datatypes into CLR datatypes in order to generate classes from MSSQL stored procedures. I'm using this chart as a reference. Before I get too far into what will probably take all day and be a huge pain to fully test, I'd like to call out to the SO community to see if anyone else has already written or found something in C# to accomplish this seemingly common and assuredly tedious task.

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  • Hiera datatypes wont load in Puppet

    - by Cole Shores
    I have spent a couple of days on this, followed the instructions on http://downloads.puppetlabs.com/docs/puppetmanual.pdf and even the Puppet Training Advanced Puppet manual. When I run a test against it, the results always come back as 'nil' and Im not sure why. I am running Puppet 3.6.1 Community Edition, with Hiera 1.2.1 on SLES 11. My puppet.conf file at /etc/puppet/puppet.conf consists of: [main] # The Puppet log directory. # The default value is '$vardir/log'. logdir = /var/log/puppet # Where Puppet PID files are kept. # The default value is '$vardir/run'. rundir = /var/run/puppet # Where SSL certificates are kept. # The default value is '$confdir/ssl'. ssldir = $vardir/ssl certificate_revocation = false [master] hiera_config=/etc/puppet/hiera.yaml reporturl = http://puppet2.vvmedia.com/reports/upload ssl_client_header = SSL_CLIENT_S_DN ssl_client_verify_header = SSL_CLIENT_VERIFY # certname = dev-puppetmaster2.vvmedia.com # ca_name = 'dev-puppetmaster2.vvmedia.com' # facts_terminus = rest # inventory_server = localhost # ca = false [agent] # The file in which puppetd stores a list of the classes # associated with the retrieved configuratiion. Can be loaded in # the separate ``puppet`` executable using the ``--loadclasses`` # option. # The default value is '$confdir/classes.txt'. classfile = $vardir/classes.txt # Where puppetd caches the local configuration. An # extension indicating the cache format is added automatically. # The default value is '$confdir/localconfig'. localconfig = $vardir/localconfig my /etc/puppet/hiera.yaml consists of: :backends: yaml :yaml: :datadir: /etc/puppet/hieradata :hierarchy: - common - database I have a directory created in /etc/puppet/hieradata and within it contains: /etc/puppet/hieradata/common.yaml :nameserver: ["dnsserverfoo1", "dnsserverfoo2"] :smtp_server: relay.internalfoo.com :syslog_server: syslogfoo.com :logstash_shipper: logstashfoo.com :syslog_backup_nfs: nfsfoo:/vol/logs :auth_method: ldap :manage_root: true and /etc/puppet/hieradata/database.yaml :enable_graphital: true :mysql_server_package: MySQL-server :mysql_client_package: MySQL-client :allowed_groups_login: extranet_users does anyone have any idea what could be causing Hiera to not load the requested values? I have tried even restarting the Master. Thanks in advance, Cole

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  • Creating multiple relationships in rails with same datatypes

    - by Lowgain
    What I am trying to do is kind of like this: I have datatypes "user" and "article" for instance. I want to have relationships between these two, but in more than one way. So for instance, I'd like to let a user "like" or "bookmark" an article. So I need to have two relations in the database, one for users liking the article, and one for users bookmarking, so making a "user_article" table for instance won't be sufficient, correct? What is the best way of going about doing this?

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  • How to return variable datatypes from a method

    - by Praesagus
    I have a method whose callers require different datatypes. I could repeat the requisite conversions a dozen times by putting them in each of the callers, but it seems much more efficient to do it once in the called method. public String myMethod(String myArg) { return DoSomething(myArg); } public Int32 myMethod(String myArg) { return Convert.ToInt32(DoSomething(myArg)); } private String DoSomething(key) { return SomeList[key]; } If I have multiple methods that pull data from SomeList and have to utilize different data types then in each I have to do a type conversion. Examples might be session variables or query or form requests or any other number of things. In VB I could say Function myMethod(myArg as String) as Variant myMethod=DoSomething(myArg) End Function Sorry if the original post was not very clear. I hope this makes more sense. Thanks

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  • How to force ADO.Net to use only the System.String DataType in the readers TableSchema.

    - by Keith Sirmons
    Howdy, I am using an OleDbConnection to query an Excel 2007 Spreadsheet. I want force the OleDbDataReader to use only string as the column datatype. The system is looking at the first 8 rows of data and inferring the data type to be Double. The problem is that on row 9 I have a string in that column and the OleDbDataReader is returning a Null value since it could not be cast to a Double. I have used these connection strings: Provider=Microsoft.ACE.OLEDB.12.0;Data Source="ExcelFile.xlsx";Persist Security Info=False;Extended Properties="Excel 12.0;IMEX=1;HDR=No" Provider=Microsoft.Jet.OLEDB.4.0;Data Source="ExcelFile.xlsx";Persist Security Info=False;Extended Properties="Excel 8.0;HDR=No;IMEX=1" Looking at the reader.GetSchemaTable().Rows[7].ItemArray[5], it's dataType is Double. Row 7 in this schema correlates with the specific column in Excel I am having issues with. ItemArray[5] is its DataType column Is it possible to create a custom TableSchema for the reader so when accessing the ExcelFiles, I can treat all cells as text instead of letting the system attempt to infer the datatype? I found some good info at this page: Tips for reading Excel spreadsheets using ADO.NET The main quirk about the ADO.NET interface is how datatypes are handled. (You'll notice I've been carefully avoiding the question of which datatypes are returned when reading the spreadsheet.) Are you ready for this? ADO.NET scans the first 8 rows of data, and based on that guesses the datatype for each column. Then it attempts to coerce all data from that column to that datatype, returning NULL whenever the coercion fails! Thank you, Keith Here is a reduced version of my code: using (OleDbConnection connection = new OleDbConnection(BuildConnectionString(dataMapper).ToString())) { connection.Open(); using (OleDbCommand cmd = new OleDbCommand()) { cmd.Connection = connection; cmd.CommandText = SELECT * from [Sheet1$]; using (OleDbDataReader reader = cmd.ExecuteReader()) { using (DataTable dataTable = new DataTable("TestTable")) { dataTable.Load(reader); base.SourceDataSet.Tables.Add(dataTable); } } } }

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  • Is there a way to effect user defined data types in MySQL?

    - by Dancrumb
    I have a database which stores (among other things), the following pieces of information: Hardware IDs BIGINTs Storage Capacities BIGINTs Hardware Names VARCHARs World Wide Port Names VARCHARs I'd like to be able to capture a more refined definition of these datatypes. For instance, the hardware IDs have no numerical significance, so I don't care how they are formatted when displayed. The Storage Capacities, however, are cardinal numbers and, at a user's request, I'd like to present them with thousands and decimal separators, e.g. 123,456.789. Thus, I'd like to refine BIGINT into, say ID_NUMBER and CARDINAL. The same with Hardware Names, which are simple text and WWPNs, which are hexstrings, e.g. 24:68:AC:E0. Thus, I'd like to refine VARCHAR into ENGLISH_WORD and HEXSTRING. The specific datatypes I made up are just for illustrative purposes. I'd like to keep all this information in one place and I'm wondering if anybody knows of a good way to hold this all in my MySQL table definitions. I could use the Comment field of the table definition, but that smells fishy to me. One approach would be to define the data structure elsewhere and use that definition to generate my CREATE TABLEs, but that would be a major rework of the code that I currently have, so I'm looking for alternatives. Any suggestions? The application language in use is Perl, if that helps.

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  • using text and ntext SQL Datatypes in RPG

    - by David Stratton
    I'll preface this with saying that I'm a .NET developer, and am NOT an RPG developer. I'm working with one of our RPG developers to come up with a solution, so any suggestions you provide will get passed to him. We have a scenario where we want our iSeries to read from a SQL Server database. One of the columns is a TEXT column. IN RPG, there is no equivalent data type to use for this. We've gone back and forth on this, and our current plan is to change course, and have our SQL Server write out a text file, which the iSeries can pick up and parse. This is, however, a last resort option, as the data in the file is sensitive, and we'd like to avoid the additional security overhead. We've already got the SQL Server locked down as tight as possible (one user only has read access to this, and that user is an iSeries user.) We don't want to have to worry about transferring files back and forth. However, at this point, we see no other option. We have no in-house Java developers, and need to do this in RPG. So I'm wondering if there are any RPG developers out there who have faced this situation and have any advice.

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  • Create a Generic IEnumerable<T> given a IEnumerable and the member datatypes

    - by ilias
    Hi, I get an IEnumerable which I know is a object array. I also know the datatype of the elements. Now I need to cast this to an IEnumerable<T, where T is a supplied type. For instance IEnumerable results = GetUsers(); IEnumerable<T> users = ConvertToTypedIEnumerable(results, typeof(User)); I now want to cast/ convert this to IEnumerable<User. Also, I want to be able to do this for any type. I cannot use IEnumerable.Cast<, because for that I have to know the type to cast it to at compile time, which I don't have. I get the type and the IEnumerable at runtime. - Thanks

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  • android saveinstance saving vector datatypes

    - by Javadid
    hi friends, I am making an application which is currently working perfectly but with only 1 problem... As we all know that the activity is destroyed and recreated when user changes the orientation of the phone... my activity needs to save a vector full of objects wen the activity is recreated... i checked the OnSaveInstance() method and found that there is no way a vector can be stored... Does any1 have a suggestion for storing vector so that i can retrieve it on recreation of Activity??? Any help will be appreciated... Thanx...

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  • User defined datatypes CANNOT be returned in web service in Jboss 5.0.1

    - by user1503117
    I am using Jboss 5.0.1, jdk 1.6.0 update 31 and implementing an EJB as a web service and my method in web service module returns an Array of JavaBean objects in my example BenefitLevel array object. When executed in JBoss it throws the following exception: 08:57:08,552 ERROR [ServiceProxy] Service error javax.xml.rpc.ServiceException: Cannot create proxy at org.jboss.ws.core.jaxrpc.client.ServiceImpl.getPort(ServiceImpl.java:359) 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.jboss.ws.core.jaxrpc.client.ServiceProxy.invoke(ServiceProxy.java:127) at $Proxy105.getCarrierWSSEIPort(Unknown Source) at org.apache.jsp.index_jsp._jspService(index_jsp.java:92) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:322) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:249) 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 org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126) at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:601) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) at java.lang.Thread.run(Thread.java:662) Caused by: java.lang.IllegalStateException: Cannot synchronize to any of these methods: public abstract stubs.BenefitLevel[] stubs.CarrierWSSEI.getActiveBenData() throws java.rmi.RemoteException OperationMetaData: qname={urn:CarrierWS/wsdl}getActiveBenData javaName=getActiveBenData style=rpc/literal oneWay=false soapAction= ReturnMetaData: xmlName=result partName=result xmlType={urn:CarrierWS/types/arrays/com/test/cas/carrier/plan/info}BenefitLevelArray javaType=com.benefitpartnersinc.cas.carrier.plan.info.BenefitLevel[] mode=OUT inHeader=false index=-1 at org.jboss.ws.metadata.umdm.OperationMetaData.eagerInitialize(OperationMetaData.java:491) at org.jboss.ws.metadata.umdm.EndpointMetaData.eagerInitializeOperations(EndpointMetaData.java:557) at org.jboss.ws.metadata.umdm.EndpointMetaData.initializeInternal(EndpointMetaData.java:541) at org.jboss.ws.metadata.umdm.EndpointMetaData.setServiceEndpointInterfaceName(EndpointMetaData.java:220) at org.jboss.ws.core.jaxrpc.client.ServiceImpl.getPort(ServiceImpl.java:345) ... 33 more 08:57:08,567 ERROR [STDERR] javax.xml.rpc.ServiceException: Cannot create proxy 08:57:08,567 ERROR [STDERR] at org.jboss.ws.core.jaxrpc.client.ServiceImpl.getPort(ServiceImpl.java:359) 08:57:08,567 ERROR [STDERR] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 08:57:08,567 ERROR [STDERR] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) 08:57:08,567 ERROR [STDERR] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) 08:57:08,567 ERROR [STDERR] at java.lang.reflect.Method.invoke(Method.java:597) 08:57:08,567 ERROR [STDERR] at org.jboss.ws.core.jaxrpc.client.ServiceProxy.invoke(ServiceProxy.java:127) 08:57:08,567 ERROR [STDERR] at $Proxy105.getCarrierWSSEIPort(Unknown Source) 08:57:08,567 ERROR [STDERR] at org.apache.jsp.index_jsp._jspService(index_jsp.java:92) 08:57:08,567 ERROR [STDERR] at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) 08:57:08,567 ERROR [STDERR] at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 08:57:08,567 ERROR [STDERR] at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369) 08:57:08,567 ERROR [STDERR] at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:322) 08:57:08,567 ERROR [STDERR] at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:249) 08:57:08,567 ERROR [STDERR] at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 08:57:08,567 ERROR [STDERR] at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) 08:57:08,567 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190) 08:57:08,567 ERROR [STDERR] at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92) 08:57:08,567 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126) 08:57:08,567 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) 08:57:08,567 ERROR [STDERR] at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 08:57:08,567 ERROR [STDERR] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) 08:57:08,567 ERROR [STDERR] at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) 08:57:08,567 ERROR [STDERR] at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:601) 08:57:08,567 ERROR [STDERR] at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) 08:57:08,567 ERROR [STDERR] at java.lang.Thread.run(Thread.java:662) 08:57:08,567 ERROR [STDERR] Caused by: java.lang.IllegalStateException: Cannot synchronize to any of these methods: public abstract stubs.BenefitLevel[] stubs.CarrierWSSEI.getActiveBenData() throws java.rmi.RemoteException OperationMetaData: qname={urn:CarrierWS/wsdl}getActiveBenData javaName=getActiveBenData style=rpc/literal oneWay=false soapAction= ReturnMetaData: xmlName=result partName=result xmlType={urn:CarrierWS/types/arrays/com/test/cas/carrier/plan/info}BenefitLevelArray javaType=com.test.cas.carrier.plan.info.BenefitLevel[] mode=OUT inHeader=false index=-1 08:57:08,567 ERROR [STDERR] at org.jboss.ws.metadata.umdm.OperationMetaData.eagerInitialize(OperationMetaData.java:491) 08:57:08,567 ERROR [STDERR] at org.jboss.ws.metadata.umdm.EndpointMetaData.eagerInitializeOperations(EndpointMetaData.java:557) 08:57:08,567 ERROR [STDERR] at org.jboss.ws.metadata.umdm.EndpointMetaData.initializeInternal(EndpointMetaData.java:541) 08:57:08,567 ERROR [STDERR] at org.jboss.ws.metadata.umdm.EndpointMetaData.setServiceEndpointInterfaceName(EndpointMetaData.java:220) 08:57:08,567 ERROR [STDERR] at org.jboss.ws.core.jaxrpc.client.ServiceImpl.getPort(ServiceImpl.java:345) 08:57:08,567 ERROR [STDERR] ... 33 more My Web client code is as follows : <%@page import="java.util.Hashtable"%> <%@page import="javax.naming.*,com.q4.*,javax.xml.rpc.Stub,stubs.CarrierWS,stubs.CarrierWSSEI,stubs.CarrierWSSEI_Impl"%> <%@page contentType="text/html" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>JSP Page</title> </head> <body> <h1>Hello World!</h1> <% try { InitialContext ic = new InitialContext( ); CarrierWS carrierws = (CarrierWS)ic.lookup("java:comp/env/service/CarrierWS"); out.println("========================" + carrierws); CarrierWSSEI sei = carrierws.getCarrierWSSEIPort(); out.println("Invoking the service please wait ............." + carrierws.getCarrierWSSEIPort()); ((Stub)sei)._setProperty(Stub.ENDPOINT_ADDRESS_PROPERTY,"http://localhost:8080/TestWS3WAR/CarrierWS"); out.println("Invoking the service please wait ............." + sei.getActiveBenData().length); } catch(Exception e) { out.println("Exception occurred : " + e.getMessage()); e.printStackTrace(); } %> </body> </html> Please help me where I am going wrong.

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  • Casting DataTypes with DirectCast, CType, TryCast

    - by Alex Essilfie
    Ever since I moved from VB6 to VB.NET somewhere in 2005, I've been using CType to do casting from one data type to another. I do this because it is simply faster, used to exist in VB6 and I do not know why I have to be using DirectCast if there is apparently no difference between them. I use TryCast once in a while because I understand that sometimes casting can fail. I however cannot get the difference between CType and DirectCast. Can anyone tell me the difference in plain simple English what the difference the two (CType and DirectCast)? Adding examples of where to use what as well would be helpful. Thanks.

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  • Using forward declarations for build in datatypes.

    - by bdhar
    I understand that wherever possible we shall use forward declarations instead of includes to speed up the compilation. I have a class Person like this. #pragma once #include <string> class Person { public: Person(std::string name, int age); std::string GetName(void) const; int GetAge(void) const; private: std::string _name; int _age; }; and a class Student like this #pragma once #include <string> class Person; class Student { public: Student(std::string name, int age, int level = 0); Student(const Person& person); std::string GetName(void) const; int GetAge(void) const; int GetLevel(void) const; private: std::string _name; int _age; int _level; }; In Student.h, I have a forward declaration class Person; to use Person in my conversion constructor. Fine. But I have done #include <string> to avoid compilation error while using std::string in the code. How to use forward declaration here to avoid the compilation error? Is it possible? Thanks.

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  • header confusion. Compiler not recognizing datatypes

    - by numerical25
    I am getting confused on why the compiler is not recognizing my classes. So I am just going to show you my code and let you guys decide. My error is this error C2653: 'RenderEngine' : is not a class or namespace name and it's pointing to this line std::vector<RenderEngine::rDefaultVertex> m_verts; Here is the code for rModel, in its entirety. It contains the varible. the class that holds it is further down. #ifndef _MODEL_H #define _MODEL_H #include "stdafx.h" #include <vector> #include <string> //#include "RenderEngine.h" #include "rTri.h" class rModel { public: typedef tri<WORD> sTri; std::vector<sTri> m_tris; std::vector<RenderEngine::rDefaultVertex> m_verts; std::wstring m_name; ID3D10Buffer *m_pVertexBuffer; ID3D10Buffer *m_pIndexBuffer; rModel( const TCHAR *filename ); rModel( const TCHAR *name, int nVerts, int nTris ); ~rModel(); float GenRadius(); void Scale( float amt ); void Draw(); //------------------------------------ Access functions. int NumVerts(){ return m_verts.size(); } int NumTris(){ return m_tris.size(); } const TCHAR *Name(){ return m_name.c_str(); } RenderEngine::cDefaultVertex *VertData(){ return &m_verts[0]; } sTri *TriData(){ return &m_tris[0]; } }; #endif at the very top of the code there is a header file #include "stdafx.h" that includes this // stdafx.h : include file for standard system include files, // or project specific include files that are used frequently, but // are changed infrequently // #include "targetver.h" #define WIN32_LEAN_AND_MEAN // Exclude rarely-used stuff from Windows headers // Windows Header Files: #include <windows.h> // C RunTime Header Files #include <stdlib.h> #include <malloc.h> #include <memory.h> #include <tchar.h> #include "resource.h" #include "d3d10.h" #include "d3dx10.h" #include "dinput.h" #include "RenderEngine.h" #include "rModel.h" // TODO: reference additional headers your program requires here as you can see, RenderEngine.h comes before rModel.h #include "RenderEngine.h" #include "rModel.h" According to my knowledge, it should recognize it. But on the other hand, I am not really that great with organizing headers. Here my my RenderEngine Declaration. #pragma once #include "stdafx.h" #define MAX_LOADSTRING 100 #define MAX_LIGHTS 10 class RenderEngine { public: class rDefaultVertex { public: D3DXVECTOR3 m_vPosition; D3DXVECTOR3 m_vNormal; D3DXCOLOR m_vColor; D3DXVECTOR2 m_TexCoords; }; class rLight { public: rLight() { } D3DXCOLOR m_vColor; D3DXVECTOR3 m_vDirection; }; static HINSTANCE m_hInst; HWND m_hWnd; int m_nCmdShow; TCHAR m_szTitle[MAX_LOADSTRING]; // The title bar text TCHAR m_szWindowClass[MAX_LOADSTRING]; // the main window class name void DrawTextString(int x, int y, D3DXCOLOR color, const TCHAR *strOutput); //static functions static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam); static INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam); bool InitWindow(); bool InitDirectX(); bool InitInstance(); int Run(); void ShutDown(); void AddLight(D3DCOLOR color, D3DXVECTOR3 pos); RenderEngine() { m_screenRect.right = 800; m_screenRect.bottom = 600; m_iNumLights = 0; } protected: RECT m_screenRect; //direct3d Members ID3D10Device *m_pDevice; // The IDirect3DDevice10 // interface ID3D10Texture2D *m_pBackBuffer; // Pointer to the back buffer ID3D10RenderTargetView *m_pRenderTargetView; // Pointer to render target view IDXGISwapChain *m_pSwapChain; // Pointer to the swap chain RECT m_rcScreenRect; // The dimensions of the screen ID3D10Texture2D *m_pDepthStencilBuffer; ID3D10DepthStencilState *m_pDepthStencilState; ID3D10DepthStencilView *m_pDepthStencilView; //transformation matrixs system D3DXMATRIX m_mtxWorld; D3DXMATRIX m_mtxView; D3DXMATRIX m_mtxProj; //pointers to shaders matrix varibles ID3D10EffectMatrixVariable* m_pmtxWorldVar; ID3D10EffectMatrixVariable* m_pmtxViewVar; ID3D10EffectMatrixVariable* m_pmtxProjVar; //Application Lights rLight m_aLights[MAX_LIGHTS]; // Light array int m_iNumLights; // Number of active lights //light pointers from shader ID3D10EffectVectorVariable* m_pLightDirVar; ID3D10EffectVectorVariable* m_pLightColorVar; ID3D10EffectVectorVariable* m_pNumLightsVar; //Effect members ID3D10Effect *m_pDefaultEffect; ID3D10EffectTechnique *m_pDefaultTechnique; ID3D10InputLayout* m_pDefaultInputLayout; ID3DX10Font *m_pFont; // The font used for rendering text // Sprites used to hold font characters ID3DX10Sprite *m_pFontSprite; ATOM RegisterEngineClass(); void DoFrame(float); bool LoadEffects(); void UpdateMatrices(); void UpdateLights(); }; The classes are defined within the class class rDefaultVertex { public: D3DXVECTOR3 m_vPosition; D3DXVECTOR3 m_vNormal; D3DXCOLOR m_vColor; D3DXVECTOR2 m_TexCoords; }; class rLight { public: rLight() { } D3DXCOLOR m_vColor; D3DXVECTOR3 m_vDirection; }; Not sure if thats good practice, but I am just going by the book. In the end, I just need a good way to organize it so that rModel recognizes RenderEngine. and if possible, the other way around.

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