{"record":{"id":"a24178db79498fc7","repo":"prestodb/presto","slug":"unsupported-encoding-a24178","errorCode":null,"errorMessage":"Unsupported encoding ","messagePattern":"Unsupported encoding ","errorType":"exception","errorClass":"IllegalArgumentException","httpStatus":null,"severity":"error","filePath":"presto-orc/src/main/java/com/facebook/presto/orc/reader/SliceSelectiveStreamReader.java","lineNumber":109,"sourceCode":"                currentReader = directReader;\n                if (dictionaryReader != null && context.isResetAllReaders()) {\n                    dictionaryReader = null;\n                    System.setProperty(\"RESET_SLICE_READER\", \"RESET_SLICE_READER\");\n                }\n                break;\n            case DICTIONARY:\n            case DICTIONARY_V2:\n                if (dictionaryReader == null) {\n                    dictionaryReader = new SliceDictionarySelectiveReader(context);\n                }\n                currentReader = dictionaryReader;\n                if (directReader != null && context.isResetAllReaders()) {\n                    directReader = null;\n                    System.setProperty(\"RESET_SLICE_READER\", \"RESET_SLICE_READER\");\n                }\n                break;\n            default:\n                throw new IllegalArgumentException(\"Unsupported encoding \" + kind);\n        }\n\n        currentReader.startStripe(timezone, stripe);\n    }\n\n    @Override\n    public void startRowGroup(InputStreamSources dataStreamSources)\n            throws IOException\n    {\n        currentReader.startRowGroup(dataStreamSources);\n    }\n\n    @Override\n    public String toString()\n    {\n        return toStringHelper(this)\n                .addValue(context.getStreamDescriptor())\n                .toString();","sourceCodeStart":91,"sourceCodeEnd":127,"githubUrl":"https://github.com/prestodb/presto/blob/55bb57d202de3b926896fa966c2c4a44c779634e/presto-orc/src/main/java/com/facebook/presto/orc/reader/SliceSelectiveStreamReader.java#L91-L127","documentation":"Thrown from startStripe's switch on the column's encoding kind (e.g. DIRECT, DICTIONARY_V2 handled; anything else falls through) — the stripe uses a slice encoding this reader cannot dispatch to, e.g. a writer-emitted encoding unsupported for varchar columns.","triggerScenarios":"Thrown at presto-orc/src/main/java/com/facebook/presto/orc/reader/SliceSelectiveStreamReader.java:109 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Rewrite the file using a standard DIRECT or DICTIONARY(_V2) encoding","Upgrade Presto to a release supporting the encoding shown in the message","Inspect footer metadata to confirm the encoding kind and rule out corruption"],"exampleFix":null,"handlingStrategy":"type-guard","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"55bb57d202de3b926896fa966c2c4a44c779634e","analyzedAt":"2026-09-04T12:50:26.162Z","contentChangedAt":"2026-09-04T12:50:26.162Z","schemaVersion":2},"datasetVersion":"2026-09-11T21:17:09.523Z"}