Hi Henry, In most SQL conventions, single quotes are for Strings, while double quotes are for identifiers.
Best, Xingcan > On Oct 31, 2018, at 7:53 PM, 徐涛 <happydexu...@gmail.com> wrote: > > Hi Experts, > When I am running the following SQL in FLink 1.6.2, I got > org.apache.calcite.sql.parser.impl.ParseException > > select > BUYER_ID, > AMOUNT, > concat( > from_unixtime(unix_timestamp(CREATE_TIME, 'EEE MMM dd > HH:mm:ss zzz yyyy'),'yyyyMMdd'), > case when 1>= 10 and 1<= 21 > then "02" else "01” > end > ) as date12 > from > vip_order > > but when I use single quotes , such as ’02’ , it does not complain > anything, it is a bit wired, because normally in SQL user can use double > quotation or single quotation equally. > I want to know it is a Flink limitation or a bug? If it is a > limitation, why? > Thank you. > > > Best > Henry