c# - Extracting count from where clause -

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i have table of movie reviews:

movieid  userid rating  72        64817   5 238       4984    4 167       48176   2 37        19841   1 122       987981  2 48      , on.... 129 143 27 177 47 201 220 12 247

if specify particular movieid, know how display userid's rated movie, along rating.

my question: if there no reviews submitted users, how display message saying so? if there no reviews, how capture characteristic? tried many things (working gui in c#):

sql = string.format("select count(1) num                       reviews                       movieid = '{0}'", textbox1.text);              cmd = new sqlcommand();             cmd.connection = db;             cmd.commandtext = sql;  object result = cmd.executescalar();  int numreviews = system.convert.toint32(result);      if (numreviews == 0)     {     messagebox.show("no reviews");     }         else         {           //i display them. got part          }

if result supposed number (count(1)), why cant assign integer variable , test that?

when debug code, error exception:

conversion failed when converting varchar value 'newmovienoreview' data type int.

on line

 result = cmd.executescalar();

update: silly mistake!! after printing in string, movieid= newmovienoreview instead of id! erik "examine in sql after call string.format()"! -resolved

the error

incorrect syntax near ')'.

is sql complaining syntax of sql command.

try

select count(1) num reviews movieid = {0}

note: no single quotes around {0} if movieid integer.

conversion failed when converting varchar value 'newmovienoreview' data type int.

you did not int result because there error executing sql statement.

note:

rather trusting whatever input in textbox1.text, should using parameterized query. otherwise, mean user enter textbox ;delete table reviews.

http://xkcd.com/327/


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