ios - How to select row in FMDB? -

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friends used fmdb , working well, tryed select single row gives me error

this code 

fmresultset *fresult= [db executequery:@"select * contents id = 1"]; [fresult next]; nslog(@"%@",[fresult stringforcolumn:@"title"]);

thank you

you should check results. example:

fmresultset *rs = [db executequery:@"select * contents id = 1"];  if (!rs) {     nslog(@"%s: executequery failed: %@", __function__, [db lasterrormessage]);     return; }  if ([rs next]) {     nsstring *title = [rs stringforcolumn:@"title"];     nslog(@"title = %@", title); } else {     nslog(@"%s: no record found", __function__); }  [rs close];

you flying blind if don't (a) check executequery return code; , (b) if failed, examine lasterrormessage know why didn't work.


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