I don't know if these are "complex queries" by defn, but they look very complex to a noob like me.
So I have a query here that will get the latest chart of customer_id=5:
$query = "SELECT c.Chart_ID, c.Chart_Notes
FROM tblchart AS c WHERE c.Customer_ID=5
ORDER BY c.Last_Edited ASC LIMIT 1";
But I have to relate it to another table that uses the Chart_ID as foreign key. How can I get the data from the tblcontent using tblchart.Chart_ID=tblcontent.Chart_ID? I couldn't just add that as:
$query = "SELECT c.Chart_ID, c.Chart_Notes, d.Content_Desc, d.Content_Title
FROM tblchart AS c, tblcontent AS d
WHERE c.Customer_ID=5 AND c.Chart_ID=d.Chart_ID
ORDER BY c.Last_Edited DESC LIMIT 1";
can I? As that would limit the search to just one...the use of LIMIT 1 is just to get the latest, but for the subsequent query (extended query), I am expecting multiple results extracted from tblcontent in addition to the first query I posted. A join, maybe, or union, or a complex query, but how? Please, can anyone help me? Thanks.
SELECT a.Chart_ID, a.Chart_Notes, c.Content_Desc, c.Content_Title
FROM tblChart a
INNER JOIN
(
SELECT Chart_ID, MAX(Last_edited) maxEdited
FROM tblChart
GROUP BY Chart_ID
) b ON a.Chart_ID = b.Chart_ID AND
a.Last_Edited = b.maxEdited
INNER JOIN tblcontent c
ON a.Chart_ID = c.Chart_ID
WHERE a.Customer_ID=5
Related
I need to adjust this query to do the search (like) in another column and another table.
See:
$query2 = "
select distinct(lances.codigo)
, datacompra
, horacompra
, cupom
from lances
, ".$tabelaCad."
where lances.idcliente = ".$tabelaCad.".id
and lances.datapgto = '0000-00-00'
and lances.horapgto = '00:00:00'
and (".$tabelaCad.".nome like '%".$cliente."%' or ".$tabelaCad.".usuario like '%".$cliente."%')
group
by lances.codigo
order
by lances.datacompra desc
, lances.horacompra desc
";
He currently searches only on: ".$tabelaCad.".nome and ".$tabelaCad.".usuario.
The variable $tabelaCad is the name of a table called cadastro, and the variable cliente is the one that receives the search POST.
I need her to look too in the column codigo from the table lances and in a new table called registro in the columns reg1 e reg2.
What would the query look like in this case? I have tried several ways and it does not work.
I am working with MySQL 5.7, still...
After a long discussion we found the last relation between the tables.
It is registro.reg1 to lances.codigo.
So the best way to solve the problem is to work with the inncer join.
You save unnecessary typing and can address the tables with aliases which is much more comfortable for writing procedures.
Here is my finished solution:
<?php
$query2 = "
select
distinct lc.codigo as codigo,
lc.datacompra as datacompra,
lc.horacompra as horacompra,
lc.cupom as cupom
from `lances` as lc
inner join `".$tabelaCad."` as ca on lc.idcliente = ca.id
inner join `registr` as ri on lc.codigo = ri.reg1
where lc.idcliente = ca.id
and lc.datapgto = '0000-00-00'
and lc.horapgto = '00:00:00'
and (ca.nome like '%".$cliente."%' or ca.usuario like '%".$cliente."%')
group
by lc.codigo
order
by lc.datacompra desc, lc.horacompra desc
";
?>
I put them in the selection because I do not know exactly what you intend to xD
I have sql query which should shows all records from table swt_modules, but it shows only first row.
$query1 = mysql_query ("SELECT swt_modules.id, swt_modules.name, swt_exam_regs.name AS exam_regs
FROM `swt_modules`
JOIN `swt_exam_regs`
USING ( `id` )
WHERE swt_exam_regs.id = swt_modules.exam_regulation
ORDER BY swt_modules.name DESC , swt_modules.id DESC
LIMIT " . $limit . "");
while ($fetch1 = mysql_fetch_array ($query1))
{
...
}
I have in this table (swt_modules) 3 rows and in each of them value of field "exam_regulation" is 1. In table swt_exam_regs I have only 1 row with 2 columns - id and name. Swt_modules.id stores id number. Which join I should use to be able to see all records?
I would also suggest using mysqli or pdo instead of the now deprecated mysql.
$query1 = mysql_query ("
SELECT
swt_modules.id,
swt_modules.name,
swt_exam_regs.name AS exam_regs
FROM swt_modules
LEFT JOIN swt_exam_regs on swt_exam_regs.id = swt_modules.exam_regulation
ORDER BY
swt_modules.name DESC,
swt_modules.id DESC
LIMIT $limit");
You need to use LEFT JOIN instead of INNER JOIN. Change your query as below. Notice that, I have removed LIMIT since you are trying to fetch all rows.
SELECT swt_modules.id, swt_modules.name, swt_exam_regs.name AS exam_regs
FROM `swt_modules`
LEFT JOIN `swt_exam_regs`
ON swt_exam_regs.id = swt_modules.exam_regulation
ORDER BY swt_modules.name DESC , swt_modules.id DESC
I am currently trying to get data from my table (mostKills by Weapon in a table with over 300 kills). Initially I did a normal query
$q = $mysql->query("SELECT * FROM `kills`") or die($mysql->error);
but when I tried to
$query2 = $mysql->query("SELECT `killerID`, COUNT(`killerID`) AS tot_kills FROM `kills` WHERE `killText` LIKE '%$gun%' GROUP BY `killerID` ORDER BY `tot_kills` DESC;") or die($mysql->error);
$kData = $query2->fetch_assoc();
$query3 = $mysql->query("SELECT `Username` FROM `players` WHERE `ID` = '" . $kData['killerID'] . "'") or die($mysql->error);
$uData = $query3->fetch_assoc();
$array[$gun]['Kills']++;
$array[$gun]['Gun'] = $gun;
$array[$gun]['BestKiller'] = $uData['Username'];
$array[$gun]['killAmount'] = $kData['tot_kills'];
function sortByKills($a, $b) {
return $b['Kills'] - $a['Kills'];
}
usort($array, 'sortByKills');
foreach($array as $i => $value)
{
// table here
}
I had to do it in a while loop, which caused there to be around 600 queries, and that is obviously not acceptable. Do you have any tips on how I can optimize this, or even turn this into a single query?
I heared JOIN is good for this, but I don't know much about it, and was wondering if you guys could help me
Try this...
I added a inner join and added a username to your select clause. The MIN() is just a way to include the username column in the select and will not have an impact on you result as long as you have just 1 username for every Killerid
SELECT `killerID`
, COUNT(`killerID`) AS tot_kills
, MIN(`Username`) AS username
FROM `kills`
INNER JOIN `players`
ON `players`.`id` = `kills`.`killerid`
WHERE `killText` LIKE '%$gun%'
GROUP BY `killerID`
ORDER BY `tot_kills` DESC
SELECT kills.killerID, count(kills.killerID) as killTotal, players.Username
FROM kills, players
WHERE kills.killText
LIKE '%$gun%'
AND players.ID` = kills.killerID
GROUP BY kills.killerID
ORDER BY kills.tot_kills DESC
Here is a good place to learn some more about joins.
http://www.sitepoint.com/understanding-sql-joins-mysql-database/
The best way is to have your own knowledge so you can be able to tune up your select queries.
Also put more indexes to your DB, and try to search and join by index.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
UNION query with codeigniter's active record pattern
I have the following code:
$language_id=$this->get_language_id($language_code);
$english_id=$this->get_language_id('en');
$query="SELECT e.label_value, t.user_id, t.votes, t.approved, t.language_value FROM labels e left outer join labels t on e.label_value=t.label_value WHERE e.language=$english_id and t.language=$language_id and (t.approved=1 or t.user_id=$user_id) and e.label_value in (select distinct label_value from labels WHERE language=$english_id order by label_value limit $start_index, 30) order by e.label_value, t.votes";
$query=$this->db->query($query);
$data=$query->result_array();
But I have got the following error:
This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'
So, I need to do the folowoing part "select distinct label_value from labels WHERE language=$english_id order by label_value offset $start limit 30" in another query. Please, help me, how can I do it using CodeIgniter?
UPDATE:
There are is table labels
(label_value, language_value, language) - PK,
user_id,
timestamp,
approved,
votes
and I need to get all queries from this table (for example, it's name is t and e) with labels t.label_value, e.label_value (is exists), e.user_id, e.votes, e.timestamp where t.label_value=e.label_value(same label), t.language=45 (english language), e.language=24 (my language) and (e.user_id=121234 or e.approved=1). But I need all entries, and if (t.label_value!=e.label_value) I need to get this entry with NULL fields.
This is a limitation of MySQL and not PHP or CI. In order to get around it, you need to wrap your sub query in an aliased sub query so it becomes a derived table:
$language_id = $this->get_language_id($language_code);
$english_id = $this->get_language_id('en');
$query = "
SELECT e.label_value, t.user_id, t.votes, t.approved, t.language_value
FROM labels e
LEFT OUTER JOIN labels t on e.label_value=t.label_value
WHERE
e.language = $english_id
AND t.language = $language_id
AND (t.approved = 1 OR t.user_id = $user_id)
AND e.label_value IN (
SELECT label_value
FROM (
SELECT DISTINCT label_value
FROM labels
WHERE language = $english_id
ORDER BY label_value
LIMIT $start_index, 30
) i
)
ORDER BY e.label_value, t.votes
";
$query = $this->db->query($query);
$data = $query->result_array();
I think that will work, let me know if it doesn't and I will take another look at it.
EDIT
I'm having a little difficulty working out exactly what you are trying to do, but I think it might be something more like this:
SELECT t.label_value, t.user_id, t.votes, t.approved, t.language_value
FROM (
SELECT DISTINCT label_value
FROM labels
WHERE language = $english_id
) e
LEFT JOIN labels t ON e.label_value = t.label_value
WHERE
t.language = $language_id
AND (t.approved = 1 OR t.user_id = $user_id)
ORDER BY t.label_value, t.votes
LIMIT $start_index, 30
If this is still not correct, please show some example rows, and the result set you would like to retrieve from those rows.
Solution:
$query = $this->db->query("
SELECT *, SUM(views.times) AS sum
FROM channel
RIGHT JOIN video
ON channel.channel_id = video.channel_id
LEFT JOIN user
ON channel.user_id = user.user_id
LEFT JOIN views
ON channel.channel_id = views.channel_id
GROUP BY channel.channel_name
ORDER BY sum DESC
");
I have a query that returns a list of items.
function getfrontpage(){
$this->db->select('*');
$this->db->from('channel');
$this->db->join('video', 'channel.channel_id = video.channel_id' , 'right');
$this->db->join('user', 'channel.user_id = user.user_id');
$this->db->group_by("channel.channel_name");
$query = $this->db->get();
return $query->result();
}
Now i'm trying to order these with the SUM from another table, how can i achieve this?
Here is a picture from that table:
I want the results to be sorted by the SUM of the total of "times" for each "channel_id"
thanks in advance
I would suggest to run this through $this->db->query() instead.
It's nice to fetch simple values through CodeIgniters AR functions. But at some situations it's simply easier to build query strings instead.
In your case:
$query = $this->db->query("
SELECT channel_id, SUM(times) AS sum
FROM channel
GROUP BY channel_id
ORDER BY sum DESC
");
You can also escape most values through db->query()!
$this->db->query("
SELECT name
FROM table_name
WHERE id = ?
", array(1));
Isn't it as simple as $this->db->order_by("channel_id", "desc");? this orders the results by channel_id in descending order.
Assuming the table displayed in your question is called times_table, and has a key of user_id, channel_id, you can use the following code to join the times_table into your query so the "times" column is available to sort by.
$this->db->join("times_table", "times.user_id=channel.user_id, times.channel_id=channel.channel_id", "left");
// You've already grouped by channel_name, so grouping by channel_id is probably not necessary.
$this->db->order_by("SUM(times_table.times) DESC");
N.B. I just guessed the name of your displayed table is times_table.