i already done everything to remove this duplicity on the database
On selecting a checkbox on the sectio "Bairros" i utilized as Array
for($m=0; $m<count($_POST["bairros"]); $m++){// LOOP 1
$pesquisar=($_POST["bairros"][$m]);
//Copy bairros(Array) and esporte (POST)
$query = "SELECT DISTINCT * FROM cadastro WHERE
(esporte1 = '".$_POST["esportes"]."' OR
esporte2 = '".$_POST["esportes"]."' OR
esporte3 = '".$_POST["esportes"]."' OR
esporte4 = '".$_POST["esportes"]."')
AND
(bairro1 = '".$pesquisar."' OR
bairro2 = '".$pesquisar."' OR
bairro3 = '".$pesquisar."' OR
bairro4 = '".$pesquisar."')
AND
ativarAparecer='sim' ORDER BY nomeCompleto ASC LIMIT 20";
$esporte= new consultar();
$esporte->executa($query);
//Loops
for($l=0; $l<$esporte->nrw; $l++){ //LOOP 2
echo $esporte->data["nomeCompleto"]."<br />";
$esporte->proximo();
} //close LOOP2
} //close LOOP1
Detail: this function object oriented, I believe that i'm doing something wrong at SQL or MYSQL, perhaps something is missing there.
SELECT DISTINCT *
Stop There. DISTINCT * can do what? Duplicate of what? it cant do that. Give it a field name to see unique values.
For example
SELECT DISTINCT nomeCompleto
Let's break this down. The DISTINCT clause will return unique sets based on the selected columns.
Let's say you have a table:
a | b | c
=========
1 | 2 | 3
1 | 1 | 3
1 | 2 | 4
Now if you SELECT DISTINCT a FROM table, you would get:
1
but if you SELECT DISTINCT a, b FROM table, you would get:
a | b
=====
1 | 2
1 | 1
That's because {1,2} is different from {1,1}, even though the a column is the same between those two sets.
Obviously, doing SELECT DISTINCT * FROM table would give you the original table because it uses all three columns as a "composition" of the unique set. If we amended the table to look like this:
a | b | c
=========
1 | 2 | 3
1 | 1 | 3
1 | 2 | 4
1 | 2 | 3
Then your result of SELECT DISTINCT * FROM table would give:
a | b | c
=========
1 | 2 | 3
1 | 1 | 3
1 | 2 | 4
because of the duplicate result set of {1, 2, 3}. However, since most tables have an auto-incrementing identifier as the primary key, there is almost always no difference between SELECT * and SELECT DISTINCT *.
Perhaps you're looking to GROUP BY a certain column?
How would I be using GROUP this in my script? Column that there are several equal records are this bairro, bairro2, bairro3, bairro4. Inside it is in numbers
bairro1 | bairro2 | bairro3 | bairro4
14 | 14 | 15 | 27
34 | 15 | 14 | 30
27 | 45 | 12 | 14
Related
I have a table like so (after doing a query on it to order it by score):
+---+-------+------+
|id | level |score |
+---+-------+------+
| 4 | 1 | 30 |
| 3 | 1 | 35 |
| 1 | 1 | 40 |
| 5 | 1 | 45 |
| 7 | 1 | 50 |
| 8 | 1 | 55 |
+---+-------+------+
I will output that to php in a while loop. So each row in the while loop will be the same as in the table above.
Essentially what I want to do is show 5 of these rows in a table (in html), with a certain row (e.g. where id=5) in the middle and have the two rows above and below it (in the correct order). This will be like a score board but only showing the user's score with the two above and two below.
E.g. say the user is id=5, I want to show
+---+-------+------+
|id | level |score |
+---+-------+------+
| 3 | 1 | 35 |
| 1 | 1 | 40 |
| 5 | 1 | 45 |
| 7 | 1 | 50 |
| 8 | 1 | 55 |
I am wondering does anyone know a way of doing this in php?
Basically
//select query output is in while loop
//get a certain row of the loop
//get the two rows above it and two rows below it
One method uses a lot of variables:
select t.*
from (select t.*,
lag(id, 1) over (order by score) as prev_id,
lag(id, 2) over (order by score) as prev_id2,
lead(id, 1) over (order by score) as next_id,
lead(id, 2) over (order by score) as next_id2
from t
) t
where 5 in (prev_id, prev_id2, next_id, next_id2, id)
order by score;
An alternative method is something like this:
(select t.*
from t
where t.score <= (select t2.score from t t2 where t2.id = 5)
order by score desc
limit 3
) union all
(select t.*
from t
where t.score > (select t2.score from t t2 where t2.id = 5)
order by score
limit 2
)
order by score;
This exactly syntax may not work in all databases, but the idea can easily be translated in whatever dialect of SQL. This also assumes that the scores are unique.
So my table looks like this:
| id | user | points |
| 1 | Sam | 1 |
| 2 | Sam | 6 |
| 3 | Phil | 1 |
The query I am currently using is:
SELECT user,COUNT(*) FROM table GROUP BY user order by COUNT(*) DESC
This returns the current value:
Sam: 2
Phil: 1
It looks like it counts the number of rows, not the total points? How can I do this?
The correct return should be Sam: 7.
Use SUM instead of COUNT
SELECT user, SUM(points) FROM table GROUP BY user
I'd like to fetch data from my 2 sql database and do some math and post the result in database
let's say my table1 is like this
+---+---+----------------------------+
| A | B | C |
+---+---+----------------------------+
| 2 | 9 | result from A*B*D*E in php |
| 1 | 8 | result from A*B*D*E in php |
| 4 | 7 | result from A*B*D*E in php |
| 3 | 6 | result from A*B*D*E in php |
| 6 | 5 | result from A*B*D*E in php |
| 6 | 5 | result from A*B*D*E in php |
| 5 | 4 | result from A*B*D*E in php |
+---+---+----------------------------+
and my table2 is like this
+---+----+
| D | E |
+---+----+
| 1 | 9 |
| 2 | 7 |
| 3 | 8 |
| 4 | 6 |
| 5 | 5 |
| 6 | 3 |
| 7 | 2 |
+---+----+
so far what i've done
// database connection
include_once("config.php");
// Query
$query = mysqli_query($conn, "SELECT * FROM table1");
$query2 = mysqli_query($conn, "SELECT * FROM table2");
//Source1
while($user_data1 = mysqli_fetch_array($query))
{
$A[] = $user_data1['A'];
$B[] = $user_data1['B'];
}
//Source2
while($user_data2 = mysqli_fetch_array($query2))
{
$D[] = $user_data2['D'];
$E[] = $user_data2['E'];
}
foreach (array_combine($A, $B) as $ValueA=> $ValueB)
{
foreach (array_combine($D, $E) as $ValueD=> $ValueE)
{
$result1 = $ValueA*$ValueB*ValueD*ValueE;
$val = 0.123;
$result2[] = $result1*$val;
}
$final result = min($result2);
echo round($final result, 2);
unset($result2);
}
I haven't inserted the database yet
still echoing for debug if the math is correct
somehow this code found some bug
for example using my database the final result only echo/showing 6 math result
because in table1 row 5 and 6 has same data
btw of course in my table1 and 2 has primary key
To change C in this case, you don't even need PHP. To UPDATE a value in MySQL with multiple tables just add them with a , when selecting the tables, like this:
UPDATE table1,table2 SET C = table1.A * table1.B * table2.D * table2.E WHERE C IS NULL;
Executing this code once will update all rows so that C = A*B*D*E as wanted where C is not yet set or NULL. If you want to update all rows you can just remove the WHERE condition
Note: Sometimes (at least for me) SQL will give a warning when having no WHERE condition in the SQL query. To bypass this just add WHERE 1=1 at the end.
Just for my understanding: you want to calculate a value for your calculation you need some data from table 1 that is clear, but also from table2 But which one? I guess you want to use the data from the same row ( so row 1 from table1 and row 1 from table2, row 2 from table 1 and row 2 from table2 ) right? Now you have an problem because when you make a select * from table You do not know in which order they give back from your database. Most time it may be the same order as you have input them, but there is no garantie. You have sayed you have an primary key on each table, how have you defined them? I guess you may have a id column, so you can join your table on that id?
i have a table temporary as follow as:
student | Data | number
-----------|---------------|--------------
1 | book | 2
1 | book | 5
1 | book | 9
2 | book | 1
2 | book | 5
i will show reduction of column in like as output column as follow as:
student | Data | number |output (number column of next row-previous line )
-----------|---------------|----------------|--------------
1 | book | 2 | 0
1 | book | 5 | 3 (result of (5-2=3)
1 | book | 9 | 4 (result of (9-5=4)
2 | book | 1 | 0
2 | book | 5 | 4 (result of (5-1=4)
how are writing of php's script is correct? because i'm confused
You didn't mention your DBMS, so this is standard SQL:
select student,
data,
number,
number - lag(number,1,number) over (partition by student order by id) as output
from the_table
order by student, id
SQLFiddle example
The following script will subtract the number from previous number for the same student. Here's how you can do it in MySQL (which doesn't support window functions.)
SELECT
t1.student,
t1.Data,
t1.number,
IF (t2.number IS NULL, 0, t1.number - MAX(t2.number)) as output
FROM
tbl t1
LEFT JOIN
tbl t2
ON
t1.student = t2.student
AND t1.number > t2.number
GROUP BY
t1.student, t1.Data, t1.number
Here's the SQL Fiddle
I'm trying to build a ranking system in a mysql database.
I've found several tutorials on ranking and items here on StackOverflow about ranking individual rows against each other.
However, my issue is that I need to group rows by a user id column, add up the values to a second column grouped by user id, then rank them against other groups of a different user id.
Here's an example of the table I'm using:
user_id km_skied date_entered
1 34 2010-08-19
3 2 2010-08-23
1 3 2010-08-13
4 23 2010-08-01
3 5 2010-08-02
The result printout would be by rank:
Skier Rank:
Rank User ID Total KM
1 1 37
2 4 23
3 3 7
Also, I was wondering how I find the rank for a specific user. Meaning, if I know what the user id is, can I give them just their rank? Like say
"Your Rank: 2 of 345"
That is the second part of this.
Anyone know how to do that?
Thanks!
Troy
Your query should look something like this. Add the ranking logic to the outer loop.
select * from
(select user_id, sum(km_skied) as km from ski group by user_id) x
order by x.km desc;
Don't know if it's an option, but you can use a temporary table for rankings as follows:
create temporary table ranks (rank int primary key auto_increment, user_id int, km int);
insert into ranks (user_id, km)
select user_id, km from (
select user_id, sum(km_skied) as km from ski group by user_id
) x order by x.km desc;
This gives you what you want:
mysql> select * from ranks;
+------+---------+------+
| rank | user_id | km |
+------+---------+------+
| 1 | 1 | 37 |
| 2 | 4 | 23 |
| 3 | 3 | 7 |
+------+---------+------+
3 rows in set (0.00 sec)
One downside to this approach is that skiers who are tied won't get the same rank.
Do the grouping in subquery and ranking of the results (using any of the methods you've found before) in outer query.
Thanks for your help guys.
I was able to come up with an answer based on the following Query:
$totalQuery = "SELECT SUM(track_length) as usertracklength, username, MAX(track_create_time) as lasttrack, count(DISTINCT track_create_time) as totaldays FROM user_tracks GROUP BY username ORDER BY usertracklength DESC";
$totalResult = mysql_query($totalQuery);
$rankResult = mysql_query($totalQuery);
$totalNumEntries = mysql_num_rows($totalResult);
Then Ouputting that to an array
// rank position array
$rankArray = array();
while ($row1 = mysql_fetch_array($rankResult)) {
$rankArray[] = $row1['username'];
}
Then finding position of that username in the array by using a foreach in php
foreach ($rankArray as $rank => $user) {
if ($user == $username) {
$yourRank = $rank+1;
}
}
It's the long way around, but I suppose it works for what I'm going for.
Was kind of hoping to get it done within the mysql query for efficiency.
Thanks!
You could try grouping to sum the Km as a first query, then follow it by a correlated subquery to find the ranks. For instance, if your values are stored in a table called "test", sum the Km values into a table called testtbl and then do the ranking.
mysql> select * from test;
+------+--------+------+
| Id | km_run | name |
+------+--------+------+
| 1 | 34 | a |
| 3 | 2 | c |
| 1 | 3 | a |
| 4 | 23 | d |
| 3 | 5 | c |
+------+--------+------+
5 rows in set (0.00 sec)
mysql> create table testtbl as
(select Id, sum(km_run) as tot
from test
group by Id);
Query OK, 3 rows affected (0.04 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> select * from testtbl;
+------+------+
| Id | tot |
+------+------+
| 1 | 37 |
| 3 | 7 |
| 4 | 23 |
+------+------+
3 rows in set (0.00 sec)
mysql> select t1.Id,t1.tot,
((select count(distinct t2.tot) from testtbl t2 where t1.tot < t2.tot)+1) as Rk from testtbl t1
order by Rk;
+------+------+------+
| Id | tot | Rk |
+------+------+------+
| 1 | 37 | 1 |
| 4 | 23 | 2 |
| 3 | 7 | 3 |
+------+------+------+
3 rows in set (0.00 sec)