[KYLIN-4977] sum(expression) 转换数据类型出现错误

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: v3.0.0
• Fix Version/s: Future
• Component/s: Query Engine
• Assignee: Unassigned
• Reporter: 陈虹
• Created: 16/Apr/21 08:05
• Updated: 16/Apr/21 08:07

Description

问题1： 使用 sum case when 的时候，数据类型转换报错：

SQL:" select unit_code, sum(case when task_type='11' then amount else 0 end ) amount1, sum(case when task_type='12' then amount else 0 end ) amount2 from im_tasks group by unit_code"

amount 是double类型，sum(amount)也是double，在查询时报错：

java.math.BigDecimal cannot be cast to java.lang.Double while executing SQL

 

问题2：加了强制转换类型，执行后超时了：

SQL:" select unit_code, sum(case when task_type='11' then amount else cast('0.0' as double) end ) amount1, sum(case when task_type='12' then amount else cast('0.0' as double) end ) amount2 from im_tasks group by unit_code"

在查询时报错：

Coprocessor passed deadline! Maybe server is overloaded as ……