So I have a table called violators, and I have 2 columns: Violation and Date. Violators:
---------------------------
Violation | Date
---------------------------
overspeeding | 2016-05-05
overloading | 2016-05-07
overspeeding | 2016-05-05
drunk driving | 2016-05-03
I want to know how many times the overspeeding occured in 2016-05-05, So the answer should be: 2016-05-05 - overspeeding - 2
And if I want to know, how many times the oversloading occured in 2016-05-07, The answer should be: 2016-05-07 - overloading - 1
there will be an entry in your table against every overspeeding
record.
so execute a sql query (eg with php)
$resultset = select * from tablename where Violation ='overspeeding' And Date ='2016-05-05'
this will give you two record so simply apply a count function on result set.in mysql with php ,it will look like this
$temp_variable_no_of_overspeeding =mysql_num_rows($resultset);
// or you can use count function if don't need those values
so will have 2 in your temp variable
i guess you are using java so do like this
ResultSet rs = ps.executeQuery();
int rowcount = 0;
if (rs.last()) {
rowcount = rs.getRow();
rs.beforeFirst(); // required to read data in while later . not rs.first()
//because the rs.next() below will move on 2nd element ,
//you will miss the first element
}
while (rs.next()) {
// do your standard per row stuff
}
I already fixed the problem: So here's the Sql query:
select Violation, count(Violation), Date_Violated from violators group by Violation, Date_Violated
Thank you guys for the help!
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