Can't select current Date, time or datetime

[Jacky Luk]

select  { fn DATE(CURRENT_DATE) };

I come up with this on my own, but I don't get why this doesn't return any rows
just success.

[Jacky Luk]

select o."PurchaseDateTime" ,    { fn DATE(CURRENT_DATE) } AS "Current"  from CRIS."orders" AS o
 where o."PurchaseDateTime" < ({ fn TIMESTAMPADD(SQL_TSI_MONTH, -3, CURRENT_TIMESTAMP)  } )  ;

Taking one step further, but this returns syntax error with the VALUES keyword
Any help please.

[Jacky Luk]

select t1."type1" AS type,  IFNULL(T2."Total",0) AS total , T2.month AS month,  IFNULL(T2."Sales",0) AS NS, 
 
 IFNULL(IFNULL(cast(T2."Sales" AS Float),0.0) / IFNULL(Cast(T2."cnt" as float),0.0) ,0.0) AS avg0, IFNULL(T2."cnt",0) AS cnt
 
from  
(select t."CustomerTypeName" AS "type1"
   from CRIS."customer_type" t) t1
 LEFT JOIN
(select S.type0 AS "type2", T.month AS month, sum(S."Sales") AS "Sales"   ,T.Total,  IFNULL(S."cnt",0) AS "cnt"
  from 
 
     ( select 'VIP会员' as "type0",   sum(od."NetSales") AS "Sales", count(c."CustomerCode") AS "cnt"
              from CRIS."customer" c 
           LEFT JOIN CRIS."orders" o ON (c."CustomerCode" = o."CustomerCode")
           LEFT JOIN CRIS."order_details" od ON (o."OrderCode" = od."OrderCode")
 
        where o."PurchaseDateTime"  > ({ fn TIMESTAMPADD(SQL_TSI_MONTH, -3, CURRENT_TIMESTAMP)  } ) 
 
           group by "type2"
           having sum(od."NetSales") >= 5000

 
  
UNION ALL
 
         select '普通会员' as "type2",   sum(od."NetSales") AS "Sales", count(c."CustomerCode") AS "cnt"
              from CRIS."customer" c 
           LEFT JOIN CRIS."orders" o ON (c."CustomerCode" = o."CustomerCode")
           LEFT JOIN CRIS."order_details" od ON (o."OrderCode" = od."OrderCode")
 
           where o."PurchaseDateTime" > ({ fn TIMESTAMPADD(SQL_TSI_MONTH, -3, CURRENT_TIMESTAMP)  } ) 
                 
 
           group by "type2"
           having sum(od."NetSales") < 5000) AS S,
 
        (select sum(od."NetSales") AS Total,    date(o."PurchaseDateTime") AS month
               from CRIS."orders" o LEFT JOIN CRIS."order_details" od ON (o."OrderCode" = od."OrderCode")
 
            where o."PurchaseDateTime" > ({ fn TIMESTAMPADD(SQL_TSI_MONTH, -3, CURRENT_TIMESTAMP)  } ) 
        ) AS T
 
    )  T2
   ON  T2."type2" = t1."type1"
 
 

This is not correct
Error code -1, SQL state 42X04: Column 'type2' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE statement then 'type2' is not a column in the target table.

This has to be something to do with the double quotation marks.
What do I do? the deadline of the project is approaching.
And I've still got heaps to do.
So please help ASAP.
Thanks
Jack