Query failure while using unsafe for query execution numeric data type column specified as sort column

Steps to reproduce
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1. Set the parameter enable.unsafe.in.query.processing = true

2. CREATE TABLE sorttable1 (empno int, empname String, designation String, doj Timestamp, workgroupcategory int, workgroupcategoryname String, deptno int, deptname String, projectcode int, projectjoindate Timestamp, projectenddate Timestamp,attendance int,utilization int,salary int) STORED BY 'org.apache.carbondata.format' tblproperties('sort_columns'='empno')

3. LOAD DATA local inpath '<CSV_path>' INTO TABLE sorttable1 OPTIONS('DELIMITER'= ',', 'QUOTECHAR'= '"')

4. select empno from sorttable1

Exception thrown
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17/05/29 08:43:20 ERROR Executor: Exception in task 0.0 in stage 6.0 (TID 12)
java.lang.NullPointerException
at org.apache.spark.sql.execution.vectorized.ColumnVector.arrayData(ColumnVector.java:858)
at org.apache.spark.sql.execution.vectorized.OffHeapColumnVector.putByteArray(OffHeapColumnVector.java:421)
at org.apache.spark.sql.execution.vectorized.ColumnVector.putByteArray(ColumnVector.java:569)
at org.apache.carbondata.spark.vectorreader.ColumnarVectorWrapper.putBytes(ColumnarVectorWrapper.java:85)
at org.apache.carbondata.core.datastore.chunk.store.impl.unsafe.UnsafeVariableLengthDimesionDataChunkStore.fillRow(UnsafeVariableLengthDimesionDataChunkStore.java:167)
at org.apache.carbondata.core.datastore.chunk.impl.VariableLengthDimensionDataChunk.fillConvertedChunkData(VariableLengthDimensionDataChunk.java:112)
at org.apache.carbondata.core.scan.result.AbstractScannedResult.fillColumnarNoDictionaryBatch(AbstractScannedResult.java:228)
at org.apache.carbondata.core.scan.collector.impl.DictionaryBasedVectorResultCollector.scanAndFillResult(DictionaryBasedVectorResultCollector.java:154)
at org.apache.carbondata.core.scan.collector.impl.DictionaryBasedVectorResultCollector.collectVectorBatch(DictionaryBasedVectorResultCollector.java:147)