Re: Parametrized query fails

>Alexander Ponomarenko <shura@bitcom.msk.ru> wrote: > :... > :Possible my bad English was the cause of your misunderstanding of my question. I > :asked about query with parameters, i.e. when I don't know in advance contents of > :field. We have in our program form like this: > :.. > :Address: _____ > :Phone: _____ > :.. > :User can type something in fields but can leave they blank. Of course, we can > :analyze address and if it is null substitute one query by another, but how this is > :inconvenient! We have tens of field, so for any possible combination we should > :have NOFIELDS^2 queries. Horrible! Is there some other way to do this? > :Thanks in advance! If you prepare your select statements, then the combinations can be reduced to NOFIELDS*2 rather than NOFIELDS^2. Furthermore, we use general purpose functions in I4gl (see Power-4gl in sig.) to reduce the combinations to 1. The programming for a query is then reduced to something like: let prep_str = "select ... from mytable where 1=1" ,critstr("mytable.address","=","'",myrecord.address,"'") ,critstr("mytable.phone","=","'",myrecord.phone,"'") ,... Parameter 1: Table column name Parameter 2: Relation operator, e.g. "=", "matches". Parameter 3 and 5: Stuff surrounding the value. Parameter 4: The value as entered by the user. If the user is looking for a particular address and a blank phone number, then the result might be: select ... from mytable where 1=1 and mytable.address = '42nd street' and mytable.phone is null ... Now, I don't know how Delphi works but, whatever you do, keep away from NOFIELDS^2 :) -- ---------------------------------------------------------------------- John H. Frantz Power-4gl: Extending Informix-4gl frantz@centrum.is http://www.strengur.is/~frantz/pow4gl.html