I am trying to create a project. That’s why I downloaded a startup template from this link. Then I tried to configure with asp.net core. I set the connection string as "Default": "User ID=postgres;Password=**********;Host=localhost;Port=5432;Database=LibraryManagementDb;Pooling=true;". and then changed UseSqlServer to UseNpgsql in LibraryManagementDbContextConfigurer class.
Hi im trying to make a notification system. Basically when i add a new row, a notification will be shown on my notificationspage realtime (i use signalR with razor pages asp.net). But for some reason when i get on that page, i get these errors: Unable to cast object of type ‘System.DBNull’ to type ‘System.DateTime’.
at myWebApp.Controllers.SpeedListener.GetAlarmList() in myWebAppControllersSpeedListener.cs:line 83
at myWebApp.Controllers.SpeedListener.ListenForAlarmNotifications() in myWebAppControllersSpeedListener.cs:line 43
Recently I’ve encountered a problem where I just had to use FromSqlRaw to my db to execute the function of one of Postgresql extensions. This function returns a single entry, and I want to get value of this entry somehow. However, for some reasons I can’t do it this way:
I am trying to send string data from one web form to another, however it throws the System.NullReferenceException error. I read in the Postgress documentation that this error means there is no data to work with. This is the code for the first form:
I have declared the following model using the EF Core fluent API:
Firebird-Fyracle supports the major
Oracle-based ERP/CRM application
“Compiere” — with virtually no change
to the Compiere code base. Fyracle has
supported Compiere since version
2.4.2b, which contained over 20,000 lines of PL/SQL. The current release,
2.5.3c, has moved most PL/SQL into stored procedures written in Java,
which is also supported by
Firebird-Fyracle.
I have a simple table with an int[] column and I would like to be able to select rows that do not contain a specified user. And I can’t figure out how to do it with SQLAlchemy. I could easily make a request in SQL: SELECT * FROM practices WHERE not (33 = any(id_user)) but have no idea how to do it using Practice.query.filter(...)
There is DataFrame.to_sql method, but it works only for mysql, sqlite and oracle databases. I cant pass to this method postgres connection or sqlalchemy engine.
What’s the best way to make psycopg2 pass parameterized queries to PostgreSQL? I don’t want to write my own escpaing mechanisms or adapters and the psycopg2 source code and examples are difficult to read in a web browser.
I have the following code, using pscyopg2: