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How many database indexes is too many?
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It depends on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since t...
How to change checkbox's border style in CSS?
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outline is very good, and it works for all input and select boxes, making this useful for ".error" classes.
– SztupY
Oct 3 '11 at 14:42
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MySQL Multiple Joins in one query?
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You can simply add another join like this:
SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_message_id = dashboard_messages.id
INNER JO...
Google Play Services Library update and missing symbol @integer/google_play_services_version
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control click -> properties -> android -> libraries, add -> select the project you just imported -> ok
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Get the new record primary key ID from MySQL insert query?
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Eg:
INSERT INTO table_name (col1, col2,...) VALUES ('val1', 'val2'...);
SELECT LAST_INSERT_ID();
This will get you back the PRIMARY KEY value of the last row that you inserted:
The ID that was generated is maintained in the server on a per-connection basis. This means that the value returne...
Inserting multiple rows in mysql
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it's also possible to use INSERT INTO Table SELECT 1, '14/05/2012', 3 UNION SELECT 2, '05/14/2012', 3. of course, this will only be better of the inserted values are coming from different tables.
– Zohar Peled
Jun 1 '15 at 9:18
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How to use android emulator for testing bluetooth application?
... virtual machine set the network adapter to 'Bridged'. ·
Start the VM and select 'Live CD VESA' at boot.
Now you need to find out the IP of this VM. Go to terminal in VM (use Alt+F1
& Alt+F7 to toggle) and use the netcfg command to find this.
Now you need open a command prompt and go to your ...
How to swap the buffers in 2 windows emacs
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If you just want to swap windows (independent on the selected one), you can use the following (defun win-swap () "Swap windows using buffer-move.el" (interactive) (if (null (windmove-find-other-window 'right)) (buf-move-left) (buf-move-right)))
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Archiving project in Xcode incorrectly creates multi-application bundle
...stall is set to No or which header files are causing the problem try this: Select the archive and click the Distribute button. Select the 'Save Built Products' option. Hit Next and Save. Browse the created directory in Finder. The 'libraries' subdirectory will identify the libraries that you need t...
How to copy from current position to the end of line in vi
...opy/paste between different instances, you can use the system clipboard by selecting the * register, so the commands become "*y$ for copying and "*p for pasting.
$ move-to-linebreak
$
y$ yank-to-linebreak
y,$
"*y$ select clipboard-register yank-to-linebreak
",*,y,$
"*p select clipboard-regist...