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Selecting empty text input using jQuery
How do I identify empty textboxes using jQuery? I would like to do it using selectors if it is at all possible. Also, I must select on id since in the real code where I want to use this I don't want to select all text inputs.
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How to randomly select rows in SQL?
...rver 2005. In my db, I have a table "customerNames" which has two columns "Id" and "Name" and approx. 1,000 results.
11 An...
How to get multiple counts with one SQL query?
...ally the same thing as a PIVOT function in some RDBMS:
SELECT distributor_id,
count(*) AS total,
sum(case when level = 'exec' then 1 else 0 end) AS ExecCount,
sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
...
Google MAP API Uncaught TypeError: Cannot read property 'offsetWidth' of null
... runs that needs to access it.
You should put your initialization code inside an onload function or at the bottom of your HTML file, just before the tag, so the DOM is completely rendered before it executes (note that the second option is more sensitive to invalid HTML).
Note, as pointed out by m...
Copying files from Docker container to host
...m a container to the host, you can use the command
docker cp <containerId>:/file/path/within/container /host/path/target
Here's an example:
$ sudo docker cp goofy_roentgen:/out_read.jpg .
Here goofy_roentgen is the container name I got from the following command:
$ sudo docker ps
CONTA...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...does a DELETE followed by an INSERT internally, which has some unexpected side effects:
A new auto-increment ID is allocated.
Dependent rows with foreign keys may be deleted (if you use cascading foreign keys) or else prevent the REPLACE.
Triggers that fire on DELETE are executed unnecessarily.
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Immutable vs Mutable types
...'m confused on what an immutable type is. I know the float object is considered to be immutable, with this type of example from my book:
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Select row with most recent date per user
...
Query:
SQLFIDDLEExample
SELECT t1.*
FROM lms_attendance t1
WHERE t1.time = (SELECT MAX(t2.time)
FROM lms_attendance t2
WHERE t2.user = t1.user)
Result:
| ID | USER | TIME | IO |
-------------...
How to prevent custom views from losing state across screen orientation changes
...lass CustomView extends View {
private int stateToSave;
...
@Override
public Parcelable onSaveInstanceState() {
//begin boilerplate code that allows parent classes to save state
Parcelable superState = super.onSaveInstanceState();
SavedState ss = new SavedState(superState);
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SQLite add Primary Key
...ered Jun 3 '09 at 17:42
Nathan RidleyNathan Ridley
31.2k2828 gold badges113113 silver badges186186 bronze badges
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