{"record":{"id":"7294afc5b385aac6","repo":"diesel-rs/diesel","slug":"not-implemented","errorCode":null,"errorMessage":"not implemented","messagePattern":"not implemented","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"critical","filePath":"diesel_infer_query/src/select.rs","lineNumber":253,"sourceCode":"        ) => {\n            if let Some(item) = name\n                .0\n                .last()\n                .and_then(|a| a.as_ident())\n                .map(|a| a.value.as_str())\n                .and_then(|k| query_source_lookup.get(k))\n            {\n                let is_left_joined = item.contains_left_join(query_source_lookup)?;\n                Ok(SelectField {\n                    ident: None,\n                    kind: Expression::Wildcard {\n                        schema: item.schema.map(|s| s.to_owned()),\n                        relation: item.name.to_owned(),\n                        is_left_joined,\n                    },\n                })\n            } else {\n                todo!()\n            }\n        }\n        SelectItem::Wildcard(_) if query_source_lookup.len() == 1 => {\n            let wildcard = query_source_lookup.values().next().expect(\"Is exactly one\");\n            Ok(SelectField {\n                ident: None,\n                kind: Expression::Wildcard {\n                    schema: wildcard.schema.map(|c| c.to_owned()),\n                    relation: wildcard.name.to_owned(),\n                    is_left_joined: false,\n                },\n            })\n        }\n        s @ SelectItem::Wildcard(_wildcard_additional_options) => Err(Error::UnsupportedSql {\n            msg: format!(\"Unsupported `SELECT` expression: `{s}`\"),\n        }),\n        s @ SelectItem::QualifiedWildcard(\n            _select_item_qualified_wildcard_kind,","sourceCodeStart":235,"sourceCodeEnd":271,"githubUrl":"https://github.com/diesel-rs/diesel/blob/6fa6ed01b24b24248ab2a611698d0a7c6a2e9120/diesel_infer_query/src/select.rs#L235-L271","documentation":"Query projection inference hit a select expression shape it cannot lower to a concrete type. The offending input is the element at this position in the select list; this is an inference limitation, not a database failure.","triggerScenarios":"Building a select query whose projection contains a `SelectItem` variant unsupported by the inference logic (e.g. complex/compound select items or wildcard with multiple query sources handled by the unimplemented branch).","commonSituations":"Using `diesel_infer_query` with unusual SELECT expressions such as aliased function results, tuples from multiple sources in a form the inferencer doesn't cover, or newer internal query representations.","solutions":["Rewrite the unsupported select expression using supported constructs","Provide an explicit type annotation instead of relying on inference","Use a hand-written queryable projection for this query"],"exampleFix":"// before\nlet data = select(unknown_complex_item).load(...);\n// after\nlet data = select((users::id, users::name)).load(...);","handlingStrategy":"fallback","validationCode":"// ensure the select projection uses only explicit columns or single-source wildcard","typeGuard":null,"tryCatchPattern":"// this is a panic (todo!()), not a Result; cannot be caught with try/catch in Rust\n// guard by testing projections in CI before production use","preventionTips":["Use simple, explicit select projections with diesel_infer_query","Pin library versions and test unusual queries before deploying","File/track the unimplemented case upstream"],"tags":["rust","diesel","panic","todo-unimplemented","query-inference"],"backgroundTag":"method-not-implemented","analyzedSha":"6fa6ed01b24b24248ab2a611698d0a7c6a2e9120","analyzedAt":"2026-09-07T01:50:13.074Z","contentChangedAt":"2026-09-07T01:50:13.074Z","schemaVersion":2},"datasetVersion":"2026-09-16T09:17:16.951Z"}