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MySQL select 10 random rows from 600K rows fast
...m AS r1 JOIN
(SELECT CEIL(RAND() *
(SELECT MAX(id)
FROM random)) AS id)
AS r2
WHERE r1.id >= r2.id
ORDER BY r1.id ASC
LIMIT 1
This supposes that the distribution of ids is equal, and that there can be gaps in the id list. See the ar...
How to use shared memory with Linux in C
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* have the file actually have the new size.
* Just writing an empty string at the current file position will do.
* Note: ...
Laravel Eloquent: How to get only certain columns from joined tables
... function user() {
return $this->belongs_to('User')->select(array('id', 'username'));
}
And don't forget to include the column you're joining on.
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Best way to work with dates in Android SQLite [closed]
...String finalDateTime = "";
SimpleDateFormat iso8601Format = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss");
Date date = null;
if (timeToFormat != null) {
try {
date = iso8601Format.parse(timeToFormat);
} catch (ParseException e) {
...
There is no ViewData item of type 'IEnumerable' that has the key 'xxx'
...ubmit click
again write before returning View()
ViewData["Submarkets"] = new SelectList(submarketRep.AllOrdered(), "id", "name");
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Timer function to provide time in nano seconds using C++
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@Bernard - That must be newly added since I last looked at this. Thanks for the heads up.
– grieve
Feb 26 '09 at 21:15
3
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Downloading an entire S3 bucket?
... here for the windows installer aws.amazon.com/cli. It picks up access key id from environment variable "AWS_ACCESS_KEY_ID" and your secret key from "AWS_SECRET_ACCESS_KEY".
– Matt Bond
Jul 18 '14 at 19:03
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how can I add the aidl file to Android studio (from the in-app billing example)
... Just to clarify. Create a directory aidl under src/main/. Then add a new package com.android.vending.billing. Then copy the aidl file into the new package. See code.google.com/p/android/issues/detail?id=56755
– Kalel Wade
Jul 26 '13 at 19:08
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MySQL - UPDATE query based on SELECT Query
...syntax:
UPDATE tableA a
INNER JOIN tableB b ON a.name_a = b.name_b
SET validation_check = if(start_dts > end_dts, 'VALID', '')
-- where clause can go here
ANSI SQL syntax:
UPDATE tableA SET validation_check =
(SELECT if(start_DTS > end_DTS, 'VALID', '') AS validation_check
FRO...
C# DropDownList with a Dictionary as DataSource
...ng "Key" and "Value" texts :
Dictionary<string, string> list = new Dictionary<string, string>();
list.Add("item 1", "Item 1");
list.Add("item 2", "Item 2");
list.Add("item 3", "Item 3");
list.Add("item 4", "Item 4");
ddl.DataSource = list;
ddl.DataTextField...