How to union 2 SQL-query in Codeigniter? [duplicate] - php

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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.

Answer 1

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.