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UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
MySQL - Rows to Columns
...ms that I'll use for the rest of this post. This will be the base table:
select * from history;
+--------+----------+-----------+
| hostid | itemname | itemvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9...
Dialog to pick image from gallery or from camera
...hoto and for picking a photo. Just show a dialog with two options and upon selection, use the appropriate code.
To take picture from camera:
Intent takePicture = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(takePicture, 0);//zero can be replaced with any action code (called ...
Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...
Sublime Text 2: Trim trailing white space on demand
...way that uses no plugins or settings and works in most situations.
Multi-Select and move cursor to the end of every line
Hold CTRL-Shift, Press Left, Right
The spaces and tabs at the end of the lines should now be selected. Press Delete or Backspace
Note - Special characters such as ( and + may ...
Using column alias in WHERE clause of MySQL query produces an error
... though, by putting the expression directly into the WHERE x IN y clause:
SELECT `users`.`first_name`,`users`.`last_name`,`users`.`email`,SUBSTRING(`locations`.`raw`,-6,4) AS `guaranteed_postcode`
FROM `users` LEFT OUTER JOIN `locations`
ON `users`.`id` = `locations`.`user_id`
WHERE SUBSTRING(`loca...
How to stop Visual Studio from opening a file on single click?
...anted to add that the button David is referring to has a tooltip: "Preview Selected Items"
– Bruce van der Kooij
Jan 11 '13 at 9:39
...
How can I select an element with multiple classes in jQuery?
I want to select all the elements that have the two classes a and b .
13 Answers
13...
How do you set the startup page for debugging in an ASP.NET MVC application?
...he start page property.
Go to the project's Properties
Go to the Web tab
Select the Specific Page radio button
Type in the desired url in the Specific Page text box
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SQLite: How do I save the result of a query as a CSV file?
... file output.
sqlite> .mode csv
sqlite> .output test.csv
sqlite> select * from tbl1;
sqlite> .output stdout
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