1. 問題描述

在Hive1.2.2版本執行如下HQL時：

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

會丟擲如下異常：

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

2. 問題分析

在Hive1.2.0版本開始增加了如下配置選項，預設值為true

hive.support.sql11.reserved.keywords

該選項的目的是：是否啟用對SQL2011保留關鍵字的支援。 啟用後，將支援部分SQL2011保留關鍵字。

3.　解決方案

從上面可以知道是因為啟用了對保留關鍵字的支援導致的，上面語句中date是保留關鍵字．所以解決方案如下：

• 棄用保留關鍵字date

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

• 棄用對保留關鍵字的支援

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配置檔案中修改配置選項：

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