Questions tagged [npgsql]
Npgsql is the .NET data provider for PostgreSQL. It allows any program developed for .NET framework to access a PostgreSQL database server. It is implemented in 100% C# code.
npgsql
2,153 questions
3
votes
0
answers
73
views
Why is this code leaking Oracle connections?
I've been using Npgsql, which uses the DbDataSource abstraction. It's really nice since commands created by it do not need explicit connections to be opened by them....
- 1,246
2
votes
1
answer
101
views
How can I mark parameter for a custom EF Core function to be encoded as column name
I want to use a json function of PostgreSQL, that is not part of NpgsqlJsonDbFunctionsExtensions
...
- 3,796
2
votes
1
answer
131
views
Postgres 23505 duplicate key exception in EF Core AddOrUpdate (race condition on initial insert)
I am encountering a duplicate key value violates unique constraint error in my ASP.NET Core application, and while I understand why it happens, I am unsure about the best practice to handle it using ...
- 45
1
vote
0
answers
73
views
EF Core + Npgsql: "column 'status' is of type application_status but expression is of type text"
I've been struggling for two days with a PostgreSQL enum type issue in Entity Framework Core. Despite all my configuration, EF Core keeps trying to send a string (`text`) to an enum column.
The ...
0
votes
0
answers
85
views
Custom primitive type collection in EF Core (8)
I have a nested entity, defined like this:
...
- 3,796
1
vote
1
answer
122
views
C# NET Core LINQ To Entities doubling subquery for sorting
I am working with EF Core 6.0 Web APi.
Npgsql.EntityFrameworkCore.PostgreSQL 6.0.29
PostgreSQL 16.3
I have database (Postgres) with musical entities and lessons. Lessons related to musical entities by ...
0
votes
0
answers
52
views
EF Core 9 Scaffolding NPGSQL - attribute tags vs modelBuilder
When I ran a scaffold command on my NPGSQL db with the typical default format I find on the web:
...
- 3,661
1
vote
0
answers
40
views
DB creation fails through the Azure web app with Azure Postgres Flexible Server
I have an Azure Postgres flexible server sitting in a VNet divided into multiple subnets. In a distinct subnet lies an azure app service I am trying to run by publishing it via gitlab. However shortly ...
- 11
0
votes
1
answer
111
views
How to resolve EF Core continuous migration error with npgsql HiLo?
I'm using Hilo with a custom sequence name. When creating migrations, EF Core always creates a migration to drop the sequence with the normal name. Since EF Core 9.0, this produces a runtime exception ...
- 751
0
votes
1
answer
270
views
How do I use TPC to generate a sequence for each inherited entity in EF Core?
I've written a BaseEntity class which defines common fields in my database. It looks something like this:
...
- 186
0
votes
0
answers
83
views
ADO.NET failure to acquire connection in an SQL Server to PostgreSQL ETL (DTS)
I'm creating in VisualStudio for Application 2022 an ETL that is migrating data from a MS-SQL Server table to another in PostgreSQL DataBase. I create the ADO.NET Destination connection (server IP, ...
- 1
1
vote
1
answer
112
views
Npgsql TimeoutException during second read command
I attempt to call two functions to retrieve data from a Postgres database like so:
SomeClass.cs
...
1
vote
0
answers
103
views
How does disabling `DatabaseFacade.AutoSavepointsEnabled` risk database corruption?
The code documentation for DatabaseFacade.AutoSavepointsEnabled warns that:
Setting this value to false should only be done ...
- 78
0
votes
1
answer
61
views
Should order of columns in index match order of columns in query?
We are using EF Core 8.0 with the Npgsql provider. We have several entities that look similar to this:
...
- 6,718
1
vote
0
answers
53
views
How can I configure DateOnly properties that are mapped to timestamp columns so that queries use appropriate precision?
I have an AccountEntity:
...
- 3,583
1
vote
1
answer
130
views
npgsql call jsonb_path_exists on string mapped jsonb
I've got a table with the filed string Data { get; set; } of type jsonb:
...
- 2,359
0
votes
1
answer
244
views
How to translate a custom extension method like PgContains to PostgreSQL ILIKE + unaccent in EF Core 9 with Npgsql?
I'm using Entity Framework Core 9 with PostgreSQL via Npgsql, and I frequently write the following query pattern to perform accent-insensitive and case-insensitive searches:
...
- 1,426
0
votes
0
answers
196
views
How to set a custom migrations history table name using builder.AddNpgsqlDbContext<AppDbContext>() method in .NET Aspire?
I'm building a .NET Aspire-based application using PostgreSQL with Entity Framework Core. I’m registering my DbContext like this as I am using ...
- 1,082
0
votes
0
answers
388
views
No such host is known when trying to connect to Postgres from C# code
I am trying to connect to Postgres 17 in my local machine yet i'm getting an error of "No such host is known".
I established a connection to the instance through DBeaver yet doing so in code ...
- 177
0
votes
1
answer
139
views
How to get single row of values from database
Reading multiple values from a Postgres database using npgsql and EF Core in an ASP.NET Core MVC view:
...
- 28.3k
1
vote
2
answers
67
views
How to pass a list of locations (longitude, latitude) to a PostgreSQL/PostGIS stored function?
I have prepared a DB fiddle for my questions and also list my SQL code below.
I have created a countries_boundaries table, which I intend to fill with .poly files ...
- 23.4k
0
votes
1
answer
73
views
0
votes
0
answers
85
views
The entity type is not mapped to a table - ignores ToJson call
I'm trying to follow the npgsql guide to map a class to a JSON column, but I cannot get past the following error:
System.InvalidOperationException: The entity type 'MainCategory' is not mapped to a ...
- 32.2k
0
votes
0
answers
74
views
How to get replication events for all databases
Replication events are displayed by ASP.NET Core 9 MVC controller according using code:
...
- 28.3k
0
votes
1
answer
74
views
Keep same connection during lifetime of dbContext
I have a case where I first want to run a direct query (using .Database.SqlQuery) to try to obtain an advisory lock. Then run another query using linq. When I run ...
- 83
0
votes
0
answers
63
views
How to convert wal log to SQL commands from given time
Postgres 14 hot standby server server is running in Debian Linux under WSL. It saves wal log from master to pg_wal directory. ...
- 28.3k
1
vote
0
answers
58
views
Npgsql EF Core @> contains operator with a JSONB column modelled as an owned entity (.ToJson)
I have a DB entity with a JSONB column, modelled as an owned entity with .ToJson(), as recommended by the Npgsql EF Core documentation.
...
- 4,476
0
votes
1
answer
76
views
Execute SQL statement after connection established in EF Core with Npgsql
I'd like to execute a specific SQL command each time after the connection to the database was successful using Entity Framework Core 9 with the Npgsql Entity Framework Core Provider.
More specifically,...
- 154
0
votes
0
answers
96
views
Limitations of database context pooling in .NET
I have a base class called BaseDbContext. I derived two classes from this: WriteDbContext and ...
- 39
3
votes
0
answers
307
views
Enum mapping with Dapper and npgsql (from Postgres enum type)
I have a bunch of enums in my Postgres database, and for now I always parsed the enums manually from string to the effective value inside my .NET code (first map to string and then convert). While ...
- 4,528
1
vote
0
answers
75
views
"42883: procedure usp_delete_announcements(integer) does not exist" while calling stored procedure with out paremeters from .NET Core
I am trying to call a PostgreSQL stored procedure with OUT parameters from my .NET Core 3.1 API to delete a record based on an ID. However, when I attempt to execute the stored procedure with OUT ...
- 11
0
votes
1
answer
118
views
Composite type parameter in PostgreSql using Npgsql,
I'm working with Npgsql and and Dapper I have some tables in PostgreSql with a composite data type:
...
- 1,760
6
votes
1
answer
875
views
Polymorphism in Entity Framework Core 9 with PostgreSQL and jsonb column
I am currently working on a database table, that shall contain some base properties of the data and one property that is a jsonb column in the database that can contain different objects that are ...
- 539
0
votes
0
answers
67
views
Compare NodaTime-Periods in EF Core
I'm building an application, using .NET (8), EF Core (8) and Postgres (16). I use nodaTime for every date or time related task and NodaTime.Periods are stored in pg ...
- 1,347
0
votes
0
answers
58
views
Multi tenancy support for Single database shared schema
We are using a single database with a shared schema multi-tenancy model, as it is the most practical way to support a large number of tenants.
Is there a recommended pattern or approach in Npgsql to ...
- 1
0
votes
0
answers
77
views
Database tool in Performance Profiler not working when program is pointed to PostgreSQL
My program in C# using Entity Framework Core I can point to a PostgreSQL or SQLite database. When pointed to PostgreSQL the Database tool of Performance Analyzer does not work. There only appear ...
0
votes
0
answers
64
views
Custom boolean predicate sort convention, is it possible?
We're using Hot Chocolate 14. .Net + EF Core 8, and PostgreSQL 13... I'd like to build a custom sort convention... but I haven't found any examples after scouring the internet.
The first example is ...
0
votes
1
answer
180
views
EFCore, NPGSQL and NodaTime throws InvalidCast exception reading timestamptz into Instant after upgrade from .Net 6 to 8
We have an existing Database First (e.g. Scaffolded) .Net 6 project attached to PostgreSQL 13 DB.
The DB has a lot of timestamptz aka TIMESTAMP WITH TIMEZONE fields. So we use NodaTime.
Time(!) came ...
0
votes
1
answer
87
views
web api connection pooling
I am using the following code with npgsql 9.0.2 inside a .net 8 web api to insert records into a table, but I am having some trouble where my database gets completely overloaded with the CPU hovering ...
- 119
1
vote
0
answers
128
views
How to compare two dates with EF Core LINQ and Npgsql?
I am struggling to get documents expiring in less than 90 days:
...
- 3,473
0
votes
0
answers
35
views
Connect ErikEJ Powertools to Google Cloud Postgres Database
Been fighting with this for some time. Normally got around this running a local copy of my database on my local machine to get around all of the Google/SSL insanity. Burned myself on at least one ...
- 31
1
vote
0
answers
42
views
Npgsql 4.1.14: call stored procedure with nullable types
I have the following PostgreSQL "function1"
function1(par1 Enum_1),
function1(par1 integer),
...
function1(par1 text)
In Npgsql V 3.2.7, the parameters ...
- 27
2
votes
0
answers
97
views
Why would npgsql be throwing two different errors for timing out?
I have an ASP.NET Core Web API using EF Core. I'm trying to implement timeout middleware as shown here:
...
- 21
0
votes
1
answer
138
views
CREATE a stored procedure using plain query text via NpgsqlConnection::ExecuteAsync
I am trying to create a stpored procedure via Npsql from C#
...
- 357
0
votes
1
answer
101
views
I see two approaches to npgsql prepares. Trying to understand the differences
I have been exploring how to access Postgres from C#. When using prepared statements ( which I almost always want to do) the website recommends the following:
Create a connection the db ...
- 143
0
votes
1
answer
80
views
-1
votes
2
answers
172
views
PostgreSQL stored procedure fails with dynamic parameters for date in Dapper
I'm using PostgreSQL with a .NET project, and I'm facing an issue executing a stored procedure through Dapper when using dynamic parameters to pass a DATE parameter....
0
votes
0
answers
137
views
How to track open database connections with Entity Framework Core 8?
I have an ASP.NET Core 8 MVC application. In production the application throws an error
Npgsql.PostgresException (0x80004005): 08P01: no more connections allowed (max_client_conn)
I am using NPGSQL ...
0
votes
1
answer
189
views
In EF Core is it possible to map a `System.Version` column keeping the type's unique sorting properties?
I'd like to make a Version-backed column in the database and order by it in queries, keeping the ordering consistent with what would be the result if run on the ...
- 947
0
votes
0
answers
50
views
Exception "System.IO.IOException" in Npgsql.dll
My project uses .NET Framework 4.0.
During the execution of a program for a certain operation, a message appears in the debugging console: An exception was raised: "System.IO.IOException" in ...
- 15