M7: SQL Server introspection (describe machinery)#7
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Bump PackageVersion to 0.3.0-preview.1 (Phase 3 owns 0.3.x) and add the pilot provider project plus its unit and integration test projects, so M7's introspection work lands in the package layout planned for it. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
SqlServerTypeMap converts sp_describe_* system type names to the exact C# type text the generator's getter set supports, so the describer and the codegen agree on one type vocabulary. Types without a supported getter (datetimeoffset, time, xml, sql_variant, spatial) map to nothing by design - they must fail describe loudly rather than promise a materialization the generated code cannot perform. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
SqlServerQueryDescriber wraps sp_describe_first_result_set: it returns each visible column's name, zero-based ordinal, reported SQL type, mapped C# type text, and nullability, and throws SqlBoundDescribeException when a column's type has no generator-supported mapping. This is the prepare-step primitive ADR 0001 reserves the database round-trip for. Integration tests run against a real SQL Server via Testcontainers, skipping locally without Docker but failing hard in CI. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
DescribeAsync now also wraps sp_describe_undeclared_parameters, returning each placeholder's name (stripped of '@' to match the C# parameter it binds to) with SQL Server's suggested type mapped through the same type vocabulary; unsupported suggestions throw. Suggested types are inferences from the expression context, not column lookups - a comparison against decimal(18,2) suggests the widened decimal(38,19). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Syntax errors, missing objects, temp tables, and ambiguous parameter usage all raise provider SqlExceptions from the sp_describe_* calls; DescribeAsync now rethrows them as SqlBoundDescribeException carrying the server's message and the offending command text, giving the prepare step one exception type to report per failing query. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Record how the describer maps sp_describe_* output, which failures are inherent SQL Server limits (temp tables, ambiguous parameters, widened suggested types, unsupported type set), and how the Testcontainers suite behaves with and without Docker. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Opens Phase 3 (0.3.0-preview.1) with the pilot provider's describe machinery — the prepare-step primitive that ADR 0001 reserves the database round-trip for.
What's here
SqlBound.SqlServer(new package):SqlServerQueryDescriber.DescribeAsync(SqlConnection, commandText)wrapssp_describe_first_result_setandsp_describe_undeclared_parameters, returning aQueryDescription:DbDataReader), name (empty for unnamed expressions), reported SQL type, mapped C# type text, nullability. No-result-set statements describe as zero columns — exactly what[SqlExecute]verification expects.@nameplaceholders with SQL Server's suggested types, names stripped of@to compare against C# method parameters.SqlServerTypeMap: SQL type names → exactly the generator's supported getter vocabulary (int,string,decimal,global::System.Guid,byte[], …). Types outside it (datetimeoffset,time,xml,sql_variant, spatial, UDTs) fail describe withSqlBoundDescribeExceptionrather than promising a materialization the generated code cannot perform.SqlBoundDescribeExceptioncarrying the server's message and the offending command text — one exception type for the prepare step to report per failing query.docs/introspection.md: mechanism plus the inherentsp_describe_*limits found while testing.Testing
Noted for M8
SQL Server's suggested parameter types are inferences, not column lookups (
Price > @minPriceagainstdecimal(18,2)suggestsdecimal(38,19)), so M8 must compare mapped CLR types, not raw SQL type names.🤖 Generated with Claude Code