[IGNITE-17333] .NET: Thin 3.0: SQL ResultSet object mapping

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0
• Component/s: platforms, thin client
• Labels: .NET ignite-3

Release Note

Add `ISql.ExecuteAsync<T>` API, which maps SQL result set data to user types.

Before that, we could insert and retrieve data in a strongly typed way with object mapping via `IRecordView<T>` API, but SQL results could only be accessed in a weakly typed way through `IgniteTuple` or `DbDataReader`. This change fills the void.

Or, to put it another way, we could use LINQ to query data in a strongly typed manner. But not every query can be expressed in LINQ, sometimes we have to use raw SQL, but result mapping is still very useful, which is now possible.

This is also the fastest way to retrieve query results (see benchmarks), because there is no LINQ translation, but compiled delegates read the data with the lowest possible overhead.

• Ignite Flags: Docs Required, Release Notes Required
• Assignee: Pavel Tupitsyn
• Reporter: Pavel Tupitsyn
• Reviewer: Igor Sapego
• Created: 07/Jul/22 17:15
• Updated: 04/Sep/24 16:19
• Resolved: 26/Jan/23 16:32

Description

Table API provides object mapping capabilities:

IRecordView<Person> mappedView = Table.GetRecordView<Person>();
Person res = await mappedView.GetAsync(...);

This is cleaner and more efficient than working with *IgniteTuple*s (less allocations and type casts).

Implement similar functionality for SQL API - see ISql.ExecuteAsync<T>.

Issue Links

• blocks: IGNITE-17343 .NET: Thin 3.0: LINQ provider
• is blocked by: IGNITE-16756 .NET: Thin 3.0: Implement SQL API
• relates to: IGNITE-18392 Thin 3.0: SQL ResultSet object mapping
• relates to: IGNITE-18478 .NET: Thin 3.0: Add ExecuteReader to SQL API
• links to: GitHub Pull Request #1584