1、类型转换cast(expr as <type>)  如： cast('1' as BIGINT) 字符串转换为数字2、if语句if(boolean testCondition, T valueTrue, T valueFalseOrNull)如果 testCondition 为 true 返回 valueTrue， 否则返回 valueFalse 或 Null如： if(1 == 1, 1, 2) 结果为13、case语句CASE WHEN a THEN b [WHEN c THEN d]* [ELSE e] END如：case when a == b then b when a == c then c else d end4、字符串连接concat(stri 查看全文

transform语句中使用php编写map-red脚本1、编写hql-- 集群上php的执行环境 set mapred.cache.archives=hdfs://host:port/pathtophp/php.tgz#home; set mapred.job.priority=VERY_HIGH; -- 添加的本地文件 add file /pathtoscript/script.php; SELECT   transform(val1, val2,...)  -- 列的分隔符   ROW FORMAT DELIMITED FIELDS TERMINATED BY&nbs 查看全文

hql中from_unixtime函数的format参数取值穷举字符含义类型示例Gera designatorTextADyyearNumber2009Mmonth in yearText & NumberJuly & 07dday in monthNumber10hhour in am/pm (1-12)Number12Hhour in day (0-23)Number0mminute in hourNumber30ssecond in minuteNumber55SmillisecondNumber978Eday in weekTextTuesdayDday in yearNumber189Fday of week in monthNumber2 (2nd Wed in July)wweek in yearNumber27Wwee 查看全文