如何在Teradata中添加日期？

Question

嗨，我想将01/01/1970添加到列中，last_hit_time_gmt的数据类型为bigint，当我运行以下查询时，我正在获取数据类型

last_hit_gmmt

与定义的数据类型名称不匹配。

   select 
    distinct STG.OMN_APND_KEY,
    STG.last_hit_time_gmt,
    IIF(STG.last_hit_time_gmt  <>0,ADD_TO_DATE(TO_DATE('01/01/1970', 'DD/MM/YYYY'),'SS',cast(STG.last_hit_time_gmt as DATE ),NULL) 
from    EDW_STAGE_CDM_SRC.STG_OMNITUREDATA STG
 WHERE
 UPPER(STG_OMNITUREDATA.EVAR41) IN 
('CONS_SUPP: CONSUMER','STORE','PURCHASE')  and 
STG.OMN_APND_KEY='61855975'

请帮我..

Answer 1

查询和数据类型与Teradata不兼容。

• 如评论中所述，您可能希望使用“ CASE”代替“ IFF”。 通用格式为

CASE WHEN *condition* THEN *result_if_true*
 ELSE *result_if_false*
END as *ColumnName*

根据评论回复进行编辑

因此，在您的查询示例中，case语句可以像...

select distinct STG.OMN_APND_KEY
     ,STG.last_hit_time_gmt
     ,CASE WHEN STG.last_hit_time_gmt = 0 THEN NULL 
       ELSE DATE '1970-01-01'
      END AS YourColName
    FROM EDW_STAGE_CDM_SRC.STG_OMNITUREDATA STG
    WHERE UPPER(STG_OMNITUREDATA.EVAR41) IN 
    ('CONS_SUPP: CONSUMER','STORE','PURCHASE')  and 
    STG.OMN_APND_KEY='61855975'

另外，如果您只是尝试更新STG.last_hit_time_gmt字段，为什么不只使用两个简单的UPDATE语句？

UPDATE EDW_STAGE_CDM_SRC.STG_OMNITUREDATA 
     SET STG.last_hit_time_gmt = DATE '1970-01-01'
    WHERE STG.last_hit_time_gmt <>  0
     AND UPPER(STG_OMNITUREDATA.EVAR41) IN 
        ('CONS_SUPP: CONSUMER','STORE','PURCHASE')  
     AND STG.OMN_APND_KEY='61855975';

    UPDATE EDW_STAGE_CDM_SRC.STG_OMNITUREDATA 
     SET STG.last_hit_time_gmt = NULL
    WHERE STG.last_hit_time_gmt =  0
     AND UPPER(STG_OMNITUREDATA.EVAR41) IN 
        ('CONS_SUPP: CONSUMER','STORE','PURCHASE')  
     AND STG.OMN_APND_KEY='61855975';