All Questions
22 questions
-1
votes
2
answers
565
views
A quick way to ORDER all IDs randomly in MySQL [closed]
I need to assign random IDs to a table. Thus, I create a mapping table as
CREATE TABLE t2
(
ID int(11) unsigned NOT NULL AUTO_INCREMENT,
SourceID int(11) unsigned NOT NULL,
UNIQUE INDEX(SourceID),
...
- 4,531
0
votes
1
answer
711
views
MySQL order by rand but result must exist different specific value
I'm trying the get random values from SQL but I want results must have minimum one specific value from one column, how can I do it?
For example;
TABLE;
id | category | name
---------------------...
- 13
2
votes
2
answers
224
views
Select random database records between subset of records having the same count(*) in a query
I have this simple query:
SELECT `value`, count(*) as `noHits`
FROM `topic`
WHERE identifier IN ('" . implode("','", array_keys($processedIdentifier)) ."')
GROUP BY `value`
...
- 21
1
vote
1
answer
4k
views
How can I create a unique and random alphanumeric string using MySQL's Default Value? (v 5.6)
I am building a MySQL database and think using implicit DEFAULTS seems very promising.
I am successfully using DEFAULT CURRENT_TIMESTAMP and DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP for ...
- 111
-1
votes
1
answer
562
views
Randomly select 4 items of a randomly selected category
I need an idea how to construct this query.
I have a web page. each time the page is refreshed, I want to select data from a random category, and to select no more than 4 random items from that ...
- 1
2
votes
3
answers
9k
views
how to replace user's names with random names?
How can I use SQL only on mysql DB to replace first and last names of real users in users table using a random name from two related tables: random_first_names and random_last_names. Our users table ...
- 131
0
votes
2
answers
1k
views
Fetch one value from random row where value is not x
I have a games table in my db, which has id column(pk) and slug column(unique) - other columns are not relevant. Now, what I'd like to get is one row, or it's slug value only, which would be random ...
- 103
1
vote
2
answers
10k
views
how to select random and unique records from mysql (in php language)
I have a question table in my database which consists the following columns
question number which ranges from 1 to 150.
question text
text for 4 options as A,B,C,and D
answer option(either a,b,c or ...
1
vote
2
answers
4k
views
How to select random row with count()
Table names:
g_number name
123 John
123 Sara
123 Michael
I want to get one RANDOM name and quantity of all names with the same g_number in one query:
SELECT name, count(*) cnt
...
- 121
1
vote
2
answers
84
views
How we can design best optimized solution: Generate huge random numbers and check in database table whether this numbers are there or not
We have one table like:
Table Name:
random_number_series
Its columns are as below:
number [numeric(10)]
name [varchar(10)]
status [tinyint(1)]
type [tinyint(1)]
...
- 107
1
vote
1
answer
3k
views
How Can Get Random 2 rows FROM EACH GROUP FROM JOINED TABLE
EXAMPLE
Table Dept:
dept_id dept_name dept_status
---------------------------------------
1 Sales 1
2 Develpment 1
3 HR 1
...
- 13
2
votes
2
answers
1k
views
Selecting random rows from database initially while preserving that order later
I am building a quiz app, in which the student can login and can select the option of give exam. I want to show multiple choice questions to students randomly.
I stored all the questions in one ...
- 31
1
vote
1
answer
805
views
mysql - select random rows with max 3 rows per parent id
I currently have a query that returns a maximum of 3 rows per parent_id. I want to enhance the query to return a maximum of 3 random rows per parent_id. This does not work for me at the moment as it ...
- 111
0
votes
1
answer
893
views
Result occurs often with fast random select query
I have this query to display 4 random photos on a website (I have it from here (when I asked for something faster than ORDER BY RAND())):
(SELECT `p1`.`id`, `p1`.`url`, `p1`.`hits`, `p1`.`...
- 161
1
vote
1
answer
1k
views
What is the most efficient way to exclude records with a particular ID in a MySQL query for random records?
I have an api endpoint that returns X amount of random posts from a table called "posts". This endpoint is used by a mobile app. It retreives random posts by doing a SELECT COUNT(*) on the posts table ...
- 119
4
votes
3
answers
8k
views
Select random 10 unique rows from MySQL database?
I have one table (questions) with 54 questions.
The students have to answer all 54 questions.
I have to show 10 questions at once, then next 10 and so on....
I have to select 10 questions ...
- 277
9
votes
2
answers
18k
views
Randomizing the Auto Increment in Mysql
We have a database, where we insert data into table whenever we receive an order from our services.
We use auto_increment to generate the ID and assign the order with the same.
This is usually same ...
- 203
1
vote
2
answers
2k
views
Perform group by with random group expression (randomly partitioning rows) MYSQL
Let's say I have a table (with millions of rows)
cat1|cat2|value
A | B| 10
...
and I want to group the data by cat1 and also split the grouping into 10 (at least roughly) equal partitions of ...
- 111
0
votes
1
answer
1k
views
Getting MySQL User Variable in Sequence, While Using ORDER BY RAND()
I am running a SELECT statement, which ultimately will be in an INSERT..SELECT statement.
I want a result like this
ID COUNTER
3 1
7 2
1 3
20 4
12 ...
- 113
0
votes
1
answer
1k
views
MySQL non-sequential primary key of certain length
what's the best way to create a non-sequential primary key of a certain length in MySQL?
I'm looking to use the primary key as a 'Pin' number which real actual human people can use to refer to the ...
- 103
8
votes
4
answers
7k
views
How do I do a complex GROUP BY in MySQL?
I have a table that contains several keys into other tables (where each key is comprised of multiple columns). I would like to be able to group rows together that have an equal key, but I don't want ...
- 799
5
votes
1
answer
6k
views
How do I make MySQL auto increment in random order?
I have a table that contains several keys into other tables (where each key is comprised of multiple columns). I would like to create a new column for each key that would be an integer such that ...
- 799