Thread: ecpg "problem" ...

ecpg "problem" ...

From
"Marc G. Fournier"
Date:
       if (ic_flag == 1) {       /*only select those non-IC/Spyder nodes that has full update set*/       EXEC SQL
DECLAREfull_dyn_node CURSOR FOR                SELECT node_name FROM NODE                WHERE dynamic_community = 'f'
ANDic_flag='n' AND machine_type!=22                AND node_id != 0 AND NODE_NAME != :nodename;       }       else{
 EXEC SQL DECLARE full_dyn_node CURSOR FOR                SELECT node_name FROM NODE                WHERE
dynamic_community= 'f'                AND node_id != 0 AND NODE_NAME != :nodename; (line#493)       }
 

the above code generates the following error:

The compiler complains:
../subapi.pgc:493: ERROR: cursor full_dyn_node already defined

since its envelop'd in an if/else clause, shouldn't it work?





Re: ecpg "problem" ...

From
Jakub Ouhrabka
Date:
hi,

i think that ecpg is only text preprocessor. it doesn't understand the c
semantics - it goes from the top to the end of the file row by row and
sees your declaration twice.

kuba

On Tue, 12 Nov 2002, Marc G. Fournier wrote:

>
>
>         if (ic_flag == 1) {
>         /*only select those non-IC/Spyder nodes that has full update set*/
>         EXEC SQL DECLARE full_dyn_node CURSOR FOR
>                  SELECT node_name FROM NODE
>                  WHERE dynamic_community = 'f' AND ic_flag='n' AND machine_type!=22
>                  AND node_id != 0 AND NODE_NAME != :nodename;
>         }
>         else{
>         EXEC SQL DECLARE full_dyn_node CURSOR FOR
>                  SELECT node_name FROM NODE
>                  WHERE dynamic_community = 'f'
>                  AND node_id != 0 AND NODE_NAME != :nodename; (line#493)
>         }
>
> the above code generates the following error:
>
> The compiler complains:
> ../subapi.pgc:493: ERROR: cursor full_dyn_node already defined
>
> since its envelop'd in an if/else clause, shouldn't it work?
>
>
>
>
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ecpg "problem" ...

From
Lee Kindness
Date:
Marc,

Marc G. Fournier writes:>         if (ic_flag == 1) {>         /*only select those non-IC/Spyder nodes that has full
updateset*/>         EXEC SQL DECLARE full_dyn_node CURSOR FOR>                  SELECT node_name FROM NODE>
     WHERE dynamic_community = 'f' AND ic_flag='n' AND machine_type!=22>                  AND node_id != 0 AND
NODE_NAME!= :nodename;>         }>         else{>         EXEC SQL DECLARE full_dyn_node CURSOR FOR>
SELECTnode_name FROM NODE>                  WHERE dynamic_community = 'f'>                  AND node_id != 0 AND
NODE_NAME!= :nodename; (line#493)>         }> > the above code generates the following error:> > The compiler
complains:>../subapi.pgc:493: ERROR: cursor full_dyn_node already defined> > since its envelop'd in an if/else clause,
shouldn'tit work?
 

Unfortuantely no, you can only ever have one "EXEC SQL DECLARE" for a
given cursor name due to ecpg/ESQL simple parsing. What you would do
in a situation like this is something like:
 if( ic_flag == 1 )     /* only select those non-IC/Spyder nodes that has full update set */   sprintf(stmt, "SELECT
node_nameFROM NODE WHERE dynamic_community = 'f' AND ic_flag = 'n' AND machine_type != 22 AND node_id != 0 AND
NODE_NAME!= %s", nodename); else   sprintf(stmt, "SELECT node_name FROM NODE WHERE dynamic_community = 'f' AND node_id
!=0 AND NODE_NAME != %s", nodename);
 
 EXEC SQL PREPARE s_statement FROM :stmt; EXEC SQL DECLARE full_dyn_node CURSOR FOR s_statement;

Regards, Lee.


Re: ecpg "problem" ...

From
Michael Meskes
Date:
On Tue, Nov 12, 2002 at 02:58:17PM -0400, Marc G. Fournier wrote:
> 
> 
>         if (ic_flag == 1) {
>         /*only select those non-IC/Spyder nodes that has full update set*/
>         EXEC SQL DECLARE full_dyn_node CURSOR FOR
>                  SELECT node_name FROM NODE
>                  WHERE dynamic_community = 'f' AND ic_flag='n' AND machine_type!=22
>                  AND node_id != 0 AND NODE_NAME != :nodename;
>         }
>         else{
>         EXEC SQL DECLARE full_dyn_node CURSOR FOR
>                  SELECT node_name FROM NODE
>                  WHERE dynamic_community = 'f'
>                  AND node_id != 0 AND NODE_NAME != :nodename; (line#493)
>         }
> ...
> since its envelop'd in an if/else clause, shouldn't it work?

By definition no. You could compare it to C preprocessor commands like
#define.

Michael
-- 
Michael Meskes
Michael@Fam-Meskes.De
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