向MS SQL Server插入十進制字段的空值時拋出BatchUpdateException

Question

我們使用標準Spring批處理JdbcBatchItemWriter將數據插入MS SQL Server。 要插入的數據（來自物料處理器的輸出）包含在Map<String,String>中，該數據包含列名和值。

對於定義爲Decimal（更具體而言，（十進制（19,5），null）的列包含空值（表示爲空字符串「」）時，會拋出以下異常：

java.sql.BatchUpdateException: Error converting data type nvarchar to numeric 

數字字段這不是小數，做工精細

的驅動程序是：net.sourceforge.jtds.jdbc.Driver

以下DLL文件用來連接到SQL Server：ntlmauth.dll

春季批處理項作家配置類似於以下內容：

<bean id="itemWriter" class="org.springframework.batch.item.database.JdbcBatchItemWriter"> 
    <property name="dataSource" ref="..." /> 
    <property name="sql" value="${...}" /> 
    <property name="itemPreparedStatementSetter"> 
     <bean class="org.springframework.batch.item.database.support.ColumnMapItemPreparedStatementSetter" /> 
    </property> 
    <property name="itemSqlParameterSourceProvider"> 
      <bean class="org.springframework.batch.item.database.BeanPropertyItemSqlParameterSourceProvider" /> 
    </property> 
</bean> 

以下是完整的堆棧跟蹤：

]; Error converting data type nvarchar to numeric.; nested exception is java.sql.BatchUpdateException: Error converting data type nvarchar to numeric. 
    at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:245) 
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:72) 
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:603) 
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:615) 
    at org.springframework.jdbc.core.JdbcTemplate.batchUpdate(JdbcTemplate.java:884) 
    at org.springframework.jdbc.core.namedparam.NamedParameterBatchUpdateUtils.executeBatchUpdateWithNamedParameters(NamedParameterBatchUpdateUtils.java:40) 
    at org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate.batchUpdate(NamedParameterJdbcTemplate.java:303) 
    at org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate.batchUpdate(NamedParameterJdbcTemplate.java:298) 
    at org.springframework.batch.item.database.JdbcBatchItemWriter.write(JdbcBatchItemWriter.java:175) 
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.writeItems(SimpleChunkProcessor.java:175) 
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.doWrite(SimpleChunkProcessor.java:151) 
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.write(SimpleChunkProcessor.java:274) 
    at org.springframework.batch.core.step.item.SimpleChunkProcessor.process(SimpleChunkProcessor.java:199) 
    at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:75) 
    at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:395) 
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130) 
    at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:267) 
    at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:77) 
    at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:368) 
    at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215) 
    at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144) 
    at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:253) 
    at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:195) 
    at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:141) 
    at org.springframework.batch.core.job.flow.JobFlowExecutor.executeStep(JobFlowExecutor.java:64) 
    at org.springframework.batch.core.job.flow.support.state.StepState.handle(StepState.java:60) 
    at org.springframework.batch.core.job.flow.support.SimpleFlow.resume(SimpleFlow.java:151) 
    at org.springframework.batch.core.job.flow.support.SimpleFlow.start(SimpleFlow.java:130) 
    at org.springframework.batch.core.job.flow.FlowJob.doExecute(FlowJob.java:135) 
    at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:301) 
    at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:134) 
    at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:48) 
    at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:127) 
    ... 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:601) 
    at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:64) 
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:53) 
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) 
    at java.util.concurrent.FutureTask$Sync.innerRunAndReset(FutureTask.java:351) 
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:178) 
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:178) 
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) 
    at java.lang.Thread.run(Thread.java:722) 
Caused by: java.sql.BatchUpdateException: Error converting data type nvarchar to numeric. 
    at net.sourceforge.jtds.jdbc.JtdsStatement.executeBatch(JtdsStatement.java:944) 
    at org.apache.commons.dbcp.DelegatingStatement.executeBatch(DelegatingStatement.java:297) 
    at org.springframework.jdbc.core.JdbcTemplate$4.doInPreparedStatement(JdbcTemplate.java:899) 
    at org.springframework.jdbc.core.JdbcTemplate$4.doInPreparedStatement(JdbcTemplate.java:884) 
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:587) 

任何幫助是極大的讚賞。

Answer 1

我還沒有使用Spring框架，但我可以說，從字符串轉換爲數字類型時，空字符串不等於NULL。剛剛嘗試這兩個查詢：

SELECT CONVERT(INT, ''); 
SELECT CONVERT(DECIMAL(19, 5), ''); 

第一（即CONVERT(INT)）返回0，而不是空。第二個失敗與你所看到的同樣的錯誤。您需要以某種方式更改映射以傳入可以等於NULL的值。如果您可以提交表達式而不是文字，則類似以下內容可能有效：

CASE WHEN '{my value}' = '' THEN NULL ELSE '{my value}' END