A clause used in SQL SELECT statements to sort query results.

learn more… | top users | synonyms

0
votes
3answers
902 views

Running an “ORDER BY CASE” query on MySQL view breaks it afterwards

Whenever I create a MySQL view and then run a query ordering the results with ORDER BY CASE WHEN (...), the view becomes unusable. The newly created view works properly and all SQL is correct. This ...
0
votes
2answers
39 views

Sorting of results is slow some times but fast at other times

I have a mysql query that is joining a few tables and then uses order by field for sorting. It sometimes runs quite fast at other times it is slow. While it was slow i profiled the query to find that ...
1
vote
0answers
57 views

MySQL query with order by decreased performance

Here is my schema: CREATE TABLE `UserMst` ( `UserID` mediumint(8) unsigned NOT NULL AUTO_INCREMENT, `EMailID` varchar(50) DEFAULT NULL, `UserName` varchar(20) DEFAULT NULL, `FullName` ...
1
vote
0answers
245 views

MySQL GROUP BY and ORDER BY giving inconsistent results

I'm currently working with WordPress, and I've added a new meta value which is a number between 0 and 30. Zero is ignored and up to 30 need to be organised in order and only the latest (based on the ...
0
votes
0answers
22 views

Mysql Show records according to their positions by grouping and order by

I am writing a query i should show the records according to the rank position given along with price order and group by sitename shopdetails id | productid | productname | sitename | siteid | ...
0
votes
0answers
72 views

group by and order by making query very slow in mysql?

Query works fast: select SQL_NO_CACHE users.id, users.name from useres left join user_statistics on users.id = user_statistics.user_id where users.is_deleted = 0 group by users.id ...
0
votes
0answers
31 views

Which of these two queries is better - can be optimized more?

With regards to the usage of the IF statement, which is better to use? Query #1: SELECT whatever FROM auctions AS a LEFT JOIN ............... WHERE ............... ORDER BY ...
0
votes
0answers
164 views

Using an enum as part of an index definition

When I use an ENUM column in a table the ORDER BY uses the ordinal of the ENUM not its value. I wasn't aware of that. So my question is what are the subtle issues when an ENUM is part of an index ...
0
votes
0answers
99 views

Slow query with ORDER BY with index created (more than 4mins on 0.6million records

I ran into a very weird query performance situation. If I run this query without order by, it finish in millsecs, with order by, it ends up with more than 4mins. EXPLAIN SELECT `book_book`.`id`, ...