Board index » delphi » Problem with DataSet.CommandText and *two* parameters

2004-08-24 08:24:10 PM
delphi190
Hi,
my problem is, in short:
I have two input-fields. Their values are passed to a
DataSet.CommandText via parameters (:sucha and :suchb) and the
query should look for combinations of the two values in the
mysql-database.
In general the query should look for
:sucha in all fields of the database ('OR' combination)
AND
:suchb in all fields of the same database (again 'OR' combination)
The query works OK when I restrict it to the first field, so it
seems to me, that the parameters are set correct and have been
assigned a correct value:
<snip>
ClientDataSet1.CommandText :='select * from `biblio` '+
'where autor like :sucha '+
'AND autor like :suchb';
<snip>
Now, when I extend the query over two fields I will get the message
that the value for the second parameter is missing and the program
stops executing:
<snip>
ClientDataSet1.CommandText :='select * from biblio '+
'where (autor like :sucha '
'OR titel like :sucha) '+
'AND (autor like :suchb'+
'OR titel like :suchb)';
<snip>
I tried all kinds of bracketing, all with the same result.
What am I doing wrong?
Thanks in advance,
Roland
Delphi6 (Update 2), MySQL 4.017
 

Hi,
I posted this already in b.p.d.d.dbexpress, but didn't receive any
answer, so this group might be more appropriate
my problem is, in short:
I have two input-fields. Their values are passed to a
DataSet.CommandText via parameters (:sucha and :suchb) and the
query should look for combinations of the two values in the
mysql-database.
In general the query should look for
:sucha in all fields of the database (with an 'OR' combination)
AND
:suchb in all fields of the same database (again with an 'OR' combination)
The query works OK when I restrict it to the first field, so it
seems to me, that both parameters are set correct and have been
assigned a correct value:
<snip>
ClientDataSet1.CommandText :='select * from `biblio` '+
'where autor like :sucha '+
'AND autor like :suchb';
<snip>
Now, when I extend the query over two fields (with AND and OR)
I'll get the message that the value for the second parameter is
missing and the program stops executing:
<snip>
ClientDataSet1.CommandText :='select * from biblio '+
'where (autor like :sucha '
'OR titel like :sucha) '+
'AND (autor like :suchb '+
'OR titel like :suchb)';
<snip>
I tried all kinds of bracketing to make the logical hierarchy of
the query unambiguous (incl. double-bracketing), all with the same
result.
What am I doing wrong?
Thanks in advance,
Roland
Delphi6 (Update 2), MySQL 4.017
 

Roland Reuss writes:
all the parameter names different, for your case
'where (autor like :sucha '
'OR titel like :sucha2) '+
'AND (autor like :suchb '+
'OR titel like :suchb2)';
Don't know about MySQL and the access components you are using but you
could at least give it a try.
Alex
 

Alex Ehrlich <XXXX@XXXXX.COM>schrieb:
Roland