mySQL Query next id with parameters - php

/id/desription/status/
--------------------
/1/testing01/ 1 /
/2/testing02/ 0 /
/3/testing03/ 1 /
/4/testing04/ 1 /
Hi,
I need to query next id where status = 1
If mySQL Query, I need query id next to id = 1 where status = 1
SELECT * WHERE id = (1 + 1) AND status = 1 ?
So my outcome is id number 3.
Thanks for the help,
appreciate lots.

How about order and limit?
SELECT * FROM table_name WHERE status = 1 AND id > 1 ORDER BY id ASC LIMIT 1;
You should look into setting the indexes correctly here also, to ensure top performance.

Related

mysql second priority where clause

So for example I have a table users, with a column 'count' and a column 'uid' which is the primary key.
uid | count
1 | 20
2 | 20
3 | 20
4 | 20
4 | 18
I want to select exactly one row which has count less than or equal to the present row. For example, I have the row where uid = 2.
Now I want to select a column which has count less than or equal to the present count value which is "20". and I want to select exactly one row which is closest to it.
Now I will have the choice to select either the row which has uid = 3 or uid = 4. In such case, I will want to select the column with the lowest uid value such that it is greater than the present uid value which is 2. Therefore I will want uid = 3 as my result.
How to put this in a mysql query ?
So something like this?
SELECT * FROM users
WHERE count <= 20
ORDER BY count DESC, uid ASC
LIMIT 1
That'll sort the results so that everything above 20 is discarded, and you get the rest in decreasing count order, with lower user ids taking priority if there are multiples of the same count. The LIMIT 1 restricts the query to return only one row.
If you want to make the comparison to an existing row, your easiest bet is to do this:
SELECT * FROM users
WHERE count <= 20
AND uid != 2
ORDER BY count DESC, uid ASC
LIMIT 1
SELECT * FROM users
WHERE count <= 20
AND uid IN (3,4)
ORDER BY uid ASC,count DESC
LIMIT 1

How to get the next row in sql

I have a table that is something like this
id | names | value
1 Vicky 43
2 Erica 23
3 Rueben 33
4 Bob 54
5 Chris 60
Then I set them in order according to their value. Now the table looks like this.
id | names | value
5 Chris 60
4 Bob 54
1 Vicky 43
3 Rueben 33
2 Erica 23
Now the starting point is id 5 which has a name of Chris and a value of 60. My goal is, to get the next row which has an id of 4 and name of Bob and a value of 54.
You just need to limit the resultset:
SELECT * from table
ORDER BY value DESC
LIMIT 1, 1
Output:
| ID | NAMES | VALUE |
|----|-------|-------|
| 4 | Bob | 54 |
Fiddle here.
The LIMIT basically works this way: the first number sets the starting point (being 0 the minimal value) and the second number the amount of items to fetch (in this case only one).
Edit:
A different way of understanding the question would be: Given a value for a particular field (EG: id field with value of 5)... what would be the previous record? As we have the id 4 in the data we should return that one.
That could be accomplished this way:
SELECT * from t
WHERE id < 5
ORDER BY id DESC
LIMIT 1
Fiddle here.
This way you can traverse the results in both orders (ASC and DESC) and also get both the next or previous (> or <) rows.
If your current ID is for example 4 then
Next:
select * from foo where id = (select min(id) from foo where id > 4)
previous:
select * from foo where id = (select max(id) from foo where id < 4)
sql server:
with temp as
(
SELECT ROW_NUMBER() OVER (ORDER BY value desc) AS ROWID, * FROM table_name
)
SELECT * from temp where ROWID=2
mysql:
SELECT * from table
ORDER BY value DESC
LIMIT 1, 1
I get the feeling that this is a PHP related question?
If that's so, then you can use PHP's mysql or mysqli_fetch functions to get what you want... along with a loop
This is your basic loop-through-a-mysql-query
$sql = mysql_query( "SELECT * from table ORDER BY value DESC" );
while ( $r = mysql_fetch_array( $sql ) ) {
echo $r['value'] . "<br />\n";
}
If you want to have them all at your disposal and be able to call either one of them at will, you will need to store the data in an accessible array, like so
$sql = mysql_query( "SELECT * from table ORDER BY value DESC" );
$theData = array();
while ( $r = mysql_fetch_array( $sql ) ) {
$theData[] = $r['value'];
}
Then, to access the SECOND value, use this
echo $theData[1];

display records after spicific id

Here the SQL query and I need some adjustment to it
SELECT DISTINCT ic.img_path, ic.id
FROM images_community ic
WHERE ic.delete_flag = 0 AND ic.status = 1
ORDER BY ( SELECT (count(id = ic.id ) + ic.views)
FROM image_comments WHERE img_id = ic.id) DESC
I need to show record after specific ID
not limit and offset for sure I need display rows after this id =5
this images retrieve
> images id | img_path
> 1 | dafad.sjdbh
> 2 | dafad.sjdbh
> 5 | dafad.sjdbh
> 3 | dafad.sjdbh
IS there a way to display records after id = 5 in the same query retrieved
You can use limit and offset to achieve it, please see Limit, Offset
If you want all rows after offset just do
SELECT DISTINCT ic.img_path, ic.id
FROM images_community ic
WHERE ic.delete_flag = 0 AND ic.status = 1
ORDER BY ( SELECT (count(id = ic.id ) + ic.views)
FROM image_comments WHERE img_id = ic.id) DESC LIMIT (SELECT cout(*) FROM table_name) OFFSET my_row_offset
Found the row position for this ID and start the Limit from it.

How can I get previous row in mysql

I have query:
SELECT ID
FROM VACANCIES
WHERE CATEGORYID = 1
AND VISIBLE = '1'
AND user_enable = '1'
AND DATA >= '2012-08-10 10:54:46'
AND torder >= 0
AND ID > 570153
ORDER BY torder ASC, DATA ASC, ID ASC
LIMIT 1
I get the result ID - 570164 as previous key and this is wrong result: correct result is 567556
570164 | ROW 1 | 2012-08-10 11:27:39
567556 | ROW 2 | 2012-08-10 10:55:53
570153 | ROW 2 | 2012-08-10 10:54:46
Is there a solution to get prev id ?
Notice:
I make order by date but date can be equal and prev id can be less than curent ID
Your condition states that the ID must be greater than 570153.
570164 is the result returned, which satisfies that condition.
567556 is the result you're hoping for, which doesn't satisfy that condition.
My guess is you want a less than rather than greater than on your ID condition, but I don't know what you're aiming for so can't be sure.
I'd also switch your sort condition from ASC to DESC on the ID column, or you'll get the first match (i.e. lowest id) rather than the one closest to the value you're comparing to.
SELECT ID
FROM VACANCIES
WHERE CATEGORYID = 1
AND VISIBLE = '1'
AND user_enable = '1'
AND DATA >= '2012-08-10 10:54:46'
AND torder >= 0
AND ID < 570153
ORDER BY torder ASC, DATA ASC, ID DESC
LIMIT 1

PHP - SQL: fetching results in round robin fashion

I have a table, which consists of 3 fields:
id
name
status
Every time I get the results, it should give me 5 names whose status = 1.
Suppose the db contains following:
id name status
1 A 1
2 B 1
3 C 0
4 D 1
5 E 0
6 F 0
7 H 1
8 I 1
9 J 1
10 K 1
11 L 1
12 M 0
1st time, fetch should return: A,B,D,H,I (5 records)
2nd time, fetch should return: J,K,L,A,B (5 records)
UPDATE: I don't want typical pagenation. Consider I have 12 available names from A1 to A12. The first fetch should return A1-A5, second fetch A6-A10 and third fetch A11, A12, A1, A2, A3. So when I reach the end, I need to get records starting from the first to fill the 5 slots.
i am doing it in php with mysql
This looks like some sort of job allocation script?
You need 2 things:
the highest ID returned last time the script was run (lastID)
a number larger than the maximum ID in the table (bigNum)
Then you can write your query as
SELECT
id, name
FROM
table
WHERE
status=1
ORDER BY
(bignum + id) MOD (bigNum + lastID + 1)
LIMIT 5
Shazaam!
Keep track of the ids of the records returned, and for the following queries do:
select top 5 *
from (
select top 5 *
from MyTable
where status = 1
and id not in (1,2,4,7,8)
order by name
union
select top 5 *
from MyTable
where status = 1
order by name
) a
$q = mysql_query("SELECT name FROM table WHERE status = 1 LIMIT 5);
while ($row = mysql_fetch_row($q))
{
.... //first 5
}
$q = mysql_query("SELECT name FROM table WHERE status = 1 LIMIT 5,5);
while ($row = mysql_fetch_row($q))
{
.... //second 5
}
this uses the offset functionality of mysql- think of it as pagination for your results.

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