Class DbExceptionClassifier

Namespace

Trellis.EntityFrameworkCore

Assembly

Trellis.EntityFrameworkCore.dll

Classifies database exceptions across providers (SQL Server, PostgreSQL, SQLite, MySQL/MariaDB). Used internally by both SaveChangesResultAsync(DbContext, CancellationToken) and SaveChangesResultAsync(DbContext, bool, CancellationToken) overloads. Also available for direct use in repositories that need custom error messages per exception type.

public static class DbExceptionClassifier

Inheritance

object

DbExceptionClassifier

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Methods

ExtractConstraintDetail(DbUpdateException)

Attempts to extract a human-readable constraint detail from the exception. Returns the constraint name or violated column if available, otherwise null.

public static string? ExtractConstraintDetail(DbUpdateException ex)

Parameters

ex DbUpdateException

The DbUpdateException to extract details from.

Returns

string

A constraint detail string, or null if no detail can be extracted.

ExtractConstraintIdentity(DbUpdateException)

Attempts to extract the database constraint identity (constraint name and table name) associated with a DbUpdateException, on a best-effort basis across SQL Server, PostgreSQL, SQLite, and MySQL/MariaDB providers. Returns (null, null) when no identity can be determined (unknown provider, missing inner exception, message format the parser does not recognise, localised provider message, etc.).

public static (string? ConstraintName, string? TableName) ExtractConstraintIdentity(DbUpdateException ex)

Parameters

ex DbUpdateException

The DbUpdateException to extract identity from.

Returns

(string ConstraintName, string TableName)

A tuple of (ConstraintName, TableName) where each element may independently be null if the provider did not surface it or the message could not be parsed.

Remarks

Typed extraction is preferred where the provider exposes the names as properties (PostgreSQL's PostgresException.ConstraintName / TableName); the SQL Server / SQLite / MySQL paths parse the message because those providers do not expose typed identity properties.

Telemetry-only. Constraint and table names can reveal schema details and should not be surfaced directly in API responses. Use the returned values for structured logging and observability dimensions (for example as the ConstraintName / ConstraintTableName payload on the Error.Conflict produced by DbContext.TryInsertUniqueAsync).

Exceptions

ArgumentNullException

Thrown when ex is null.

IsDuplicateKey(DbUpdateException)

Returns true if the exception represents a unique constraint violation (duplicate key).

public static bool IsDuplicateKey(DbUpdateException ex)

Parameters

ex DbUpdateException

The DbUpdateException to classify.

Returns

bool

true if this is a duplicate key violation; otherwise false.

IsForeignKeyViolation(DbUpdateException)

Returns true if the exception represents a foreign key constraint violation.

public static bool IsForeignKeyViolation(DbUpdateException ex)

Parameters

ex DbUpdateException

The DbUpdateException to classify.

Returns

bool

true if this is a foreign key violation; otherwise false.