Release Notes

[Preview Release 6.1.0-preview1.25120.4] - 2025-04-30

This update brings the following changes over the previous release:

We thank the following public contributors. Their efforts toward this project are very much appreciated.

Added packet multiplexing support to improve large data read performance. #2714 #3161 #3202
Added support for special casing with Fabric endpoints. #3084

Fixed distributed transactions to be preserved during pooled connection resets. #3019.
Fixed application crash when the Data Source parameter begins with a comma. #3250.
Resolved synonym count discrepancies in debug mode. #3098.
Addressed warnings for down-level SSL/TLS versions. #3126.

Optimized binary size for AOT. #3091
Refined bulk copy operations to handle unmatched column names more effectively. #3205.
Enhanced SqlBulkCopy to explicitly identify mismatched column names. #3183.
Optimized outgoing SSPI blob handling using IBufferWriter<byte>. #2452.
Replaced byte[] with string for SNI to improve efficiency. #2790.
Code cleanup to remove SQL 2000 support. #2839, #3206, #3217
Connection pool design refactor for a modular connection pool design. #3199
Updated various dependencies #3229, primarily:
- System.Text.Encodings.Web to v8.0.0
- System.Text.Json to v8.0.5
- Azure.Identity to v1.13.2
- Microsoft.Identity.Model.Json.Web.Tokens to v7.7.1
- Microsoft.Identity.Model.Protocols.OpenIdConnect to v7.7.1
Code merge towards a unified SqlClient project, aligning .NET Framework and .NET Core implementations. (#2957, #2963, #2984, #2982, #3023, #3015, #2967, #3164, #3163, #3171, #3182, #3179, #3156, #3213, #3232, #3236, #3231, #3241, #3246, #3247, #3222, #3255, #3254, #3259, #3264, #3256, #3251, #3275, #3277, #3263, #3292, #3208).
Test improvements include updates to test references, removal of hardcoded certificates, improved stability, and better coverage (#3041, #3034, #3130, #3128, #3181, #3060, #3184, #3033, #3186, #3025, #3230, #3237, #3059, #3061).