Failed to recognize predicate 'xxx'. Failed rule: 'identifier' in column specifi

1. 问题描述

在Hive1.2.2版本运行如下HQL时：

select dt as date, comMap['searchType'] as search_type, comMap['clickType'] as click_type
from search_click
where dt = '20170614';

会抛出如下异常：

Failed to recognize predicate 'date'. Failed rule: 'identifier' in column specification

2. 问题分析

在Hive1.2.0版本开始增加了如下配置选项，默认值为true：

hive.support.sql11.reserved.keywords

该选项的目的是：是否启用对SQL2011保留关键字的支持。 启用后，将支持部分SQL2011保留关键字。

3.　解决方案

从上面可以知道是因为启用了对保留关键字的支持导致的，上面语句中date是保留关键字．所以解决方案如下：

• 弃用保留关键字date

select dt, comMap['searchType'] as search_type, comMap['clickType'] as click_type
from search_click
where dt = '20170614';

• 弃用对保留关键字的支持

sudo -uwirelessdev hive -e "
   set hive.support.sql11.reserved.keywords = false ;
   select dt, comMap['searchType'] as search_type, comMap['clickType'] as click_type
   from search_click
   where dt = '20170614';
" > a.txt

或者在conf下的hive-site.xml配置文件中修改配置选项：

<property>
    <name>hive.support.sql11.reserved.keywords</name>
    <value>false</value>
</property>