Обсуждение: ecpg "problem" ...
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?
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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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.
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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