Could someone give me a sample about haskelldb?
Hi, I am learning it following the very few documents on its site. Well, I failed, with the import modules, I still cannot compile it. The error is on "T.*". 6 import Database.HaskellDB.HDBC.SQLite3 7 import Database.HaskellDB 8 import Database.HaskellDB.DBSpec 9 import Database.HaskellDB.DBSpec.PPHelpers 10 import Database.HaskellDB.Query 48 q = do 49 t <- table $ Table "notes" [] 50 restrict ( t!T.done .<>. False ) 51 r <- project ( T.subject << t!T.subject ) 52 order [ desc r T.priority 53 , desc r T.dt ] 54 return r -- 竹密岂妨流水过 山高哪阻野云飞
I changed it, some other problem occured.
1. How to compare a BoolT column to a True? "t!c .<>. True" could not work.
2. What shoud I use after "!"? Like table!col, recordset!col, what is col?
Thanks.
On Fri, Jun 19, 2009 at 1:24 PM, Magicloud
Magiclouds
Hi, I am learning it following the very few documents on its site. Well, I failed, with the import modules, I still cannot compile it. The error is on "T.*".
6 import Database.HaskellDB.HDBC.SQLite3 7 import Database.HaskellDB 8 import Database.HaskellDB.DBSpec 9 import Database.HaskellDB.DBSpec.PPHelpers 10 import Database.HaskellDB.Query
48 q = do 49 t <- table $ Table "notes" [] 50 restrict ( t!T.done .<>. False ) 51 r <- project ( T.subject << t!T.subject ) 52 order [ desc r T.priority 53 , desc r T.dt ] 54 return r -- 竹密岂妨流水过 山高哪阻野云飞
-- 竹密岂妨流水过 山高哪阻野云飞
Hi Magicloud, restrict (t!T.done .<>. constant False) should dot it but your t!T.done confuses me, is the the T.xxx due to an import? also the line 49 does not seem to be right. Would you mind to post your table and column definitions? Günther Magicloud Magiclouds schrieb:
I changed it, some other problem occured. 1. How to compare a BoolT column to a True? "t!c .<>. True" could not work. 2. What shoud I use after "!"? Like table!col, recordset!col, what is col? Thanks.
On Fri, Jun 19, 2009 at 1:24 PM, Magicloud Magiclouds
wrote: Hi, I am learning it following the very few documents on its site. Well, I failed, with the import modules, I still cannot compile it. The error is on "T.*".
6 import Database.HaskellDB.HDBC.SQLite3 7 import Database.HaskellDB 8 import Database.HaskellDB.DBSpec 9 import Database.HaskellDB.DBSpec.PPHelpers 10 import Database.HaskellDB.Query
48 q = do 49 t <- table $ Table "notes" [] 50 restrict ( t!T.done .<>. False ) 51 r <- project ( T.subject << t!T.subject ) 52 order [ desc r T.priority 53 , desc r T.dt ] 54 return r -- 竹密岂妨流水过 山高哪阻野云飞
participants (2)
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Günther Schmidt -
Magicloud Magiclouds