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MySQL select 10 random rows from 600K rows fast
How can I best write a query that selects 10 rows randomly from a total of 600k?
26 Answers
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In MySQL, can I copy one row to insert into the same table?
...e) but I want to do this without having to list all the columns after the "select", because this table has too many columns.
...
Find a string by searching all tables in SQL Server Management Studio 2008
...T NULL
BEGIN
SET @ColumnName = ''
SET @TableName =
(
SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_N...
How to show all privileges from a user in oracle?
...
You can try these below views.
SELECT * FROM USER_SYS_PRIVS;
SELECT * FROM USER_TAB_PRIVS;
SELECT * FROM USER_ROLE_PRIVS;
DBAs and other power users can find the privileges granted to other users with the DBA_ versions of these same views. They are cov...
Adding additional data to select options using jQuery
...
HTML Markup
<select id="select">
<option value="1" data-foo="dogs">this</option>
<option value="2" data-foo="cats">that</option>
<option value="3" data-foo="gerbils">other</option>
</select&...
T-SQL get SELECTed value of stored procedure
...UTPUT parameter and a result set
ALSO, watch out if you use the pattern: SELECT @Variable=column FROM table ...
if there are multiple rows returned from the query, your @Variable will only contain the value from the last row returned by the query.
RETURN VALUE
since your query returns an int fie...
Select + copy text in a TextView?
Is there a way to allow the user to select / copy text in a TextView? I need the same functionality of EditText where you can long-press the control and get the popup options of select all / copy, but I need the control to look like a TextView.
...
Linq to Entities - SQL “IN” clause
... be used interchangeably depending on your preference:
Query Syntax:
var selected = from u in users
where new[] { "Admin", "User", "Limited" }.Contains(u.User_Rights)
select u
foreach(user u in selected)
{
//Do your stuff on each selected user;
}
Method Syntax:...
Get records with max value for each group of grouped SQL results
...
There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. T...
How to create a SQL Server function to “join” multiple rows from a subquery into a single delimited
...
If you're using SQL Server 2005, you could use the FOR XML PATH command.
SELECT [VehicleID]
, [Name]
, (STUFF((SELECT CAST(', ' + [City] AS VARCHAR(MAX))
FROM [Location]
WHERE (VehicleID = Vehicle.VehicleID)
FOR XML PATH ('')), 1, 2, '')) AS Locations
FROM [...
