{"record":{"id":"bce7cf0e3670c4a1","repo":"apache/flink","slug":"cannot-use-custom-partitioner-for-a-non-grouped-gr-bce7cf","errorCode":null,"errorMessage":"Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce)","messagePattern":"Cannot use custom partitioner for a non-grouped GroupReduce \\(AllGroupReduce\\)","errorType":"validation","errorClass":"IllegalArgumentException","httpStatus":null,"severity":"error","filePath":"flink-core/src/main/java/org/apache/flink/api/common/operators/base/PartitionOperatorBase.java","lineNumber":107,"sourceCode":"    }\n\n    public void setOrdering(Ordering ordering) {\n        this.ordering = ordering;\n    }\n\n    public Ordering getOrdering() {\n        return ordering;\n    }\n\n    public void setDistribution(DataDistribution distribution) {\n        this.distribution = distribution;\n    }\n\n    public void setCustomPartitioner(Partitioner<?> customPartitioner) {\n        if (customPartitioner != null) {\n            int[] keys = getKeyColumns(0);\n            if (keys == null || keys.length == 0) {\n                throw new IllegalArgumentException(\n                        \"Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce)\");\n            }\n            if (keys.length > 1) {\n                throw new IllegalArgumentException(\n                        \"Cannot use the key partitioner for composite keys (more than one key field)\");\n            }\n        }\n        this.customPartitioner = customPartitioner;\n    }\n\n    @Override\n    public SingleInputSemanticProperties getSemanticProperties() {\n        return new SingleInputSemanticProperties.AllFieldsForwardedProperties();\n    }\n\n    // --------------------------------------------------------------------------------------------\n\n    @Override","sourceCodeStart":89,"sourceCodeEnd":125,"githubUrl":"https://github.com/apache/flink/blob/2f3c205e9266cb30240eb7f4fdab15cad629a70f/flink-core/src/main/java/org/apache/flink/api/common/operators/base/PartitionOperatorBase.java#L89-L125","documentation":"Error \"Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce)\" thrown in apache/flink.","triggerScenarios":"Triggered at runtime when the operation fails because: Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce).","commonSituations":"Commonly caused by misconfiguration, missing dependencies or files, unsupported types or operations, or invalid user input leading to: Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce).","solutions":["Address the cause reported by the error message: Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce)","Verify the inputs, configuration values, and classpath/dependency setup related to this operation, then retry."],"exampleFix":"Correct the condition described (\"Cannot use custom partitioner for a non-grouped GroupReduce (AllGroupReduce)\") and rerun the job or command.","handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"2f3c205e9266cb30240eb7f4fdab15cad629a70f","analyzedAt":"2026-08-14T08:48:24.518Z","schemaVersion":2},"datasetVersion":"2026-08-14T10:17:34.591Z"}