I try to setup connection to SQL Server and catch the error
var
GFireDACConnProp : TSQLDBFireDACConnectionProperties;
GFFireDACConn: TSQLDBFireDACConnection;
begin
try
GFireDACConnProp := TSQLDBFireDACConnectionProperties.Create('MSSQL?Server=server','dbname','user','pass');
GFFireDACConn := TSQLDBFireDACConnection.Create(GFireDACConnProp);
// OR I := GFireDACConnProp.Execute('Select * from Station', []);
GFFireDACConn.Connect;
....
Error message:
Project app_.exe raised exception class Exception with message 'Object factory for class {3E9B315B-F456-4175-A864-B2573C4A2101} is
missing. To register it, you can drop component [TFDPhysXXXDriverLink]
into your project'.
What is correct way to connect to SQL Server and expose REST service?
FireDAC is more helpful than some other frameworks in that when things go wrong the exception messages often say how to fix the problem.
So, in your case, given that the message says "you can drop component [TFDPhysXXXDriverLink] into your project" the thing to try first would be to drop the relevant DriverLink component onto your form/datamodule. As you're using Sql Server, the the driver link to choose would be the TFDPhysMSSqlDriverLink, which is on the FireDAC Links tab of the Component Palette.
If you're creating a Console application, obviously there's no form or datamodule to drop the link on. In that case, create it in code:
FDPhysMSSQLDriverLink := TFDPhysMSSQLDriverLink.Create(Nil);
I know its an old thread, but if other come by, it can be fixed just by adding the FireDAC's units to your uses clause e.g.
uses
FireDAC.Phys.MSSQL, FireDAC.Stan.Def, FireDAC.Stan.Pool, FireDAC.DApt, FireDAC.Stan.Async; // Not sure if you need them all, FireDAC will ask for them
Related
I am having issues attempting to connect to two different databases in one Qt Application. I have my information database that stores all the information collected by the application and the new Log database which allows me to track all the changes that occur to the Application, button presses, screen loads etc, for easy debugging after its release. Separately, the databases work perfectly, but when I try to use both of them, only one will work. I read that this could be because I wasn't naming the connections and obviously only the most recently connected database could use the default connection. However when I give the databases names they wont work at all, isOpen() will return true on both, but as soon as they attempt to execute a query I get the errors
"QSqlQuery::prepare: database not open"
"QSqlError(-1, "Driver not loaded", "Driver not loaded")"
My two database declarations are:
database_location = filepath.append("/logger.sqlite");
logDB = QSqlDatabase::addDatabase("QSQLITE", "LoggerDatabaseConnection");
logDB.setHostName("localhost");
logDB.setDatabaseName(database_location);
for the Logger Database connection and :
database_location = filepath.append("/db.sqlite");
db = QSqlDatabase::addDatabase("QSQLITE", "NormalDB");
db.setHostName("localhost");
db.setDatabaseName(database_location);
Also when I am running the first query on the databases to see if their tables exist I am using
QSqlQuery query("LoggerDatabaseConnection");
and likewise for the normal database, but I am still getting connection issues even after declaring the database connection to run the query on.
The database used for the application is declared as a static QSqlDatabase in a namespace to create a global effect, so everyone can access it, that was a previous programmer, and I created the Log database as Singleton with a private database connection. Like I said both versions of the code work separately but when they are together they are fighting each other. I know there is a huge debate over the proper design of Singleton vs Dependecy Injection, but again the code works separately so I am happy with how it is designed for now. If there is any missing information or if you have any ideas, please let me know. Thank you.
QSqlQuery query("LoggerDatabaseConnection");
The first parameter of the constructor is the query, not the connection name. It will use the default connection since you specified no database object.
Try something like this:
QSqlQuery query1("YourFirstQuery", db);
QSqlQuery query2("YourSecondQuery", logDB);
Important: Also do not forget to open and close the database before / after using it by calls to QSqlDatabase::open() and QSqlDatabase::close().
The correct way to have multiple databases is to not use the pointer returned from the static addConnection method. You should use the connectionName argument:
https://doc.qt.io/qt-5/qsqldatabase.html#addDatabase-1 during initilization and query usage:
example:
void MyClass::initDb(QString dbPath, QString connName)
{
// initial db usage, etc
QSqlDatabase db = QSqlDatabase::addDatabase(YOUR_DRIVER, connName);
db.setDatabaseName(dbPath);
// open it, etc
}
void MyClass::updateThing(QString val, QString name, QString connName)
{
QString q = QString("UPDATE THINGS SET val=%1 WHERE name=%2").arg(val, name);
// add the reference to your database via the connection name
QSqlDatabase db = QSqlDatabase::database(connName);
QSqlQuery query(db);
query.exec(q);
// handle the query normally, etc
}
I'm creating a rptlibrary to share with all the reports in my company.
The library has an oda datasource created and shared to all reports. We want to do some querys from ReportEventAdapter.initialize() to the database to get information from the database. I can acces the datasource in the library in this way:
ReportDesignHandle rdh = (ReportDesignHandle)reportContext.getReportRunnable().getDesignHandle();
DesignSessionImpl ds = rdh.getModule().getSession();
String rsf = ds.getResourceFolder( );
LibraryHandle libhan = ds.openLibrary(rsf + "/my.rptlibrary" ).handle( );
DataSourceHandle datasource = libhan.findDataSource("myDS");
But once I have the datasource, there's no way to get a connection to the database from the datasource. The only way to do this, is creating a classic JDBC connection to the database using the data from the datasource? Is there any way to use a more elegant method to connect to the database from the java handler? Like using pooling, reusing the connection, etc..
Thanks.
We can iterate over dataset values in a report script event, thus if a dataset is defined with a JNDI URL, queries can take advantage of a connection pool.
However it is quite complicated. There is a full example in this topic: the script defined in "getDefaultValueList" event of the report parameter can be moved anywhere in the report and then initialize a global variable. In particular we could move it to "initialize" event, or to "beforeFactory" event (in your case "beforeFactory" is probably what you want).
We've trying recently to use XML-RPC.Net library on our project.
Both server(.Net Remoting) and client have been made according to the instructions we've found on http://xml-rpc.net/.
The connection has been made, we obtain data from the server and so on.
As the title states, now, we'd like to know how to make our XML-RPC server instance, which is created after the first client call, be able to give feedback to a WPF UI.
What we'd like to accomplish is to register an event on a server property so the call could arrive to the UI thread.
We are open to any suggestions in this regard.
Here is the code that registers the channel on server side:
IDictionary props = new Hashtable();
props["name"] = "SubsetHttpChannel";
props["port"] = 5678;
channel = new System.Runtime.Remoting.Channels.Http.HttpChannel(
props,
null,
new XmlRpcServerFormatterSinkProvider()
);
ChannelServices.RegisterChannel(channel, false);
RemotingConfiguration.RegisterWellKnownServiceType( typeof(SubsetServer), "subsetserver.rem", WellKnownObjectMode.Singleton);
This is the code that shows how we'd like to set the property after Server instance is created on the UI:
Server = new SubsetServer();
Server.Machine.OnChangeState += delegate(State actual, State next, Event pEvent)
{
uiWindowInstance.PostMessage(string.Format("Subset Server: {0} -> {1}", actual.Name, next.Name));
};
Technologies used: VS2012, WPF 4.5 and XML-RPC.NET 2.5.0
Thanks in Advance
Thanks to anyone that took the time to read it and try to answer.
I found a solution that fits me for the moment. I'd like to share it with you in the hope someone could give any hints wheter this is a solution that may generate problems in the future.
After analyzing, I found out that both server instances run in the same process. So I've created a Singleton as a property inside my Server.
I've put whatever I need inside the Singleton, so for the delegate I'd like to use in my question, the code now is:
Server = new SubsetServer();
Server.**singleton**.Machine.OnChangeState += delegate(State actual, State next, Event pEvent)
{
uiWindowInstance.PostMessage(string.Format("Subset Server: {0} -> {1}", actual.Name, next.Name));
};
Hope this helps anyone else.
Please comment if you find any flaws.
I'm trying to create a connection to an Interbase ToGo database, at runtime, in a unit that does not have a form.
MyConnection := TSQLConnection.Create(nil);
strTestPath := TPath.Combine(TPath.GetDocumentsPath, 'ISHMAEL.GDB');
MyConnection.Params.Add('Database=' + strTestPath);
MyConnection.DriverName := 'IBToGo';
MyConnection.Params.Add('User_Name=SYSDBA');
MyConnection.Params.Add('Password=masterkey');
MyConnection.Open();
Everything seems fine as I step through, until I try and open the connection. The open raises an I/O error, saying that database.gdb isn't found. I called the database ISHMAEL, so is something else happening, or is the error message misleading?
Ideally, I'd like to get all of my database calls (and really, most if not all of the business logic) out of the forms and into some data access and business object units, but am having difficulty finding examples.
All of the examples and tutorials I have found focus on dropping controls on a form, and using visual live bindings.
Can this be done inside a non-form unit?
Thanks!
I'm using Yii Framework to create my project. I need to export some data from MySQL (my project) to an external Microsoft SQL server which is on the same network.
Basically, the user needs to click on a button (which will do the export-insert) in my view and the results should be displayed - Success (if the query has been successful) or Failure (if something went wrong).
The results part is quite easy as I'll be using 'setFlash' to display the appropriate message but I want to know how to insert data into an external database through Yii.
Do you have any idea how this can be done?
Well, I agree with #SuVeRa on the first part of defining two db instances in the config.php but i don't think the sql Commands part is necessary (Plus i hate writing sql :D )
Instead you can do:
class SomeModel extends CActiveRecord
{
...
// Override the getDbConnection() function to use the ms sql db connection
public function getDbConnection()
{
return Yii::app()->ms_sql_db_connection; // The name of the connection in config.php
}
public function transfer()
{
// Here you can do all the transferring logic using normal Yii Active Record functions
}
}
Check out the docs on getDbConnection().