Re: HELP : Informix and Delphi

Delphi 2.01 Informix SE ver 5 I have to same problem. The time delay only seems to occur when I use a parameter. When I build the SQL code I do not have this problem. Does anyone have any idea why this whould cause a problem. From Adam Sorati asorati@link.com.au Michael Silver wrote: > > We use Delphi extensively with Informix. My first suggestion is to test > these same SQLs on the server to determine if Delphi or Informix is the > problem. There are also several ways of running these queries. Since > your query is dynamic, unless you are going to update the parameter, you > may as well hard code the value into the SQL. Parameters are only good > if you will be running the same query multiple times with different > parameter values each time. > > Also, be careful the way you reference the parameter. Usually > ParamByName is preferred since there is little room for error. Since > you only have one, it is not a big deal. > > What kind of response do you get with LIKE instead of matches? > > ...Michael... > > }---------- > }From: Michel CURE[SMTP:Michel.Cure@wanadoo.fr] > }Sent: Tuesday, March 04, 1997 4:19 AM > }To: informix-list@rmy.emory.edu > }Subject: HELP : Informix and Delphi > } > }I have many problems with dynamic queries from Delphi 2.01, using > }SQL-LINKS 3.5 and Informix IConnect 7.2. My server is a Informix SE v5 > }database. > }Actually, I have problems with string parameters : > } > }- If I open a dynamic query with a restriction on an indexed integer > }column, no problems : > } (Table SER has 100000 lines) > } Query.SQL.Add('select * from ser '); > } Query.SQL.ADD(' where num_ser = :num'); > } Query.Params[0].AsInteger := 123; > } Query.Prepare; > } Query.Open; > } > } -> Answer is immediate > } > } - If I open e dynamic query with a restriction on an indexed string > }column (declared as CHAR(20)) > } on Informix database : (Table MAL has 45000 lines) > } > } Query.SQL.Add('select * from mal'); > } Query.SQL.Add(' where nom_mal = :nom'); > } Query.Params[0].AsString := 'DUPONT'; > } Query.Prepare; > } Query.Open; > } > } -> Answer after a long minute > } > } - The same query with the KeyWord "matches" answers immediately !!! > } > } Query.SQL.Add('select * from mal'); > } Query.SQL.Add(' where nom_mal matches :nom'); > } Query.Params[0].AsString := 'DUPONT'; > } Query.Prepare; > } Query.Open; > } > } -> Answer immediate !!!! > } > } > } - If I open a query on table MAL with a restriction on a unique > }indexed string column (declared as > } CHAR(6)), I have problems : > } > } Rmq : column Mal.num_dos is a string column but contains only > }number characters which are considered > } as a string > } > } Query.SQL.Add('select * from mal'); > } Query.SQL.Add(' where num_dos = :nodos'); > } Query.Params[0].AsString := '123425'; > } Query.Prepare; > } Query.Open; > } > } -> Answer after a long minute > } > } - I have tried the same keyword "matches" as it worked well with > }column Mal.nom_mal > } > } Query.SQL.Add('select * from mal'); > } Query.SQL.Add(' where num_dos matches :nodos'); > } Query.Params[0].AsString := '123425'; > } Query.Prepare; > } Query.Open; > } > } -> Answer after 8 seconds! > } > } > }I really can't understand what's the matter !! > }Does anyone know the same problems? > } > }Thank You > } > }Beatrice > }