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silly doubt in mysql c api program

Hi friends,
First of all thanks for everyone who had helpe me in writing the program using mysql api. I have completed almosy every part. Now one part remains. How can I capture the case of an empty result set returned by the "SELECT query" to show the info " INFO:: EMPTY result set" back to the user. I am using the below query to retreive the rows...I tried mysql_fetch_row, and mysql_field_count function, but can't capture an empty result set.

t=mysql_real_query(mysql,query,(unsigned int) strlen(query));
if (t)
{
printf("Error making query: %s\n",
mysql_error(mysql));
}
else printf("Query made...\n");
res=mysql_use_result(mysql);
for(r=0;r<=mysql_field_count(mysql);r++){
row=mysql_fetch_row(res);
if(row<0) break;
for(t=0;t<mysql_num_fields(res);t++){
printf("%s ",row[t]);
}
printf("\n");
}

regards

NP

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joele23

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ankuratvb

>I tried mysql_fetch_row, and mysql_field_count function, but can't capture an empty result set.

mysql_field_count will return the no .of columns in the row.

For ur problem,u need the no. of rows.which would be 0 when an empty set is returned.

ankuratvb

try using mysql_num_rows to retrieve the no. of rows.

Also,what u could do,is move to the next record in the set.
If it is NULL,then this set is either one with one record or an empty recordset.

All u have to do is check how to differentiate b/w the set with one record and an empty set.

ankuratvb

Hi,

Try looking at these links on using mysql_num_rows.

http://www.mysql.com/doc/en/mysql_num_rows.html
http://www.hk8.org/old_web/linux/sql/ch19_01.htm