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HTML5 Canvas vs. SVG vs. div
...ample, let's say I want to create a rectangle, circle and polygon and then select those objects and move them around.
8 Ans...
How to get disk capacity and free space of remote computer
...t Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Select-Object Size,FreeSpace
$disk.Size
$disk.FreeSpace
To extract the values only and assign them to a variable:
$disk = Get-WmiObject Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Foreach-Obje...
Paste in insert mode?
... where register can be:
+ for the clipboard,
* for the X clipboard (last selected text in X),
" for the unnamed register (last delete or yank in Vim),
or a number of others (see :h registers).
Ctrl-R {register} inserts the text as if it were typed.
Ctrl-R Ctrl-O {register} inserts the text wit...
What's the difference between VARCHAR and CHAR?
...CHAR(10),
Street VARCHAR(10));
Insert into temp
values('Pune','Oxford');
select length(city), length(street) from temp;
Output will be
length(City) Length(street)
10 6
Conclusion: To use storage space efficiently must use VARCHAR Instead CHAR if variable length is ...
'0000-00-00 00:00:00' can not be represented as java.sql.Timestamp error
...o update the values, or while these modifications take place, you can do a select using a case/when.
SELECT CASE ModificationDate WHEN '0000-00-00 00:00:00' THEN '1970-01-01 01:00:00' ELSE ModificationDate END AS ModificationDate FROM Project WHERE projectId=1;
...
How to add 'ON DELETE CASCADE' in ALTER TABLE statement
...ARE
CURSOR consCols (theCons VARCHAR2, theOwner VARCHAR2) IS
select * from user_cons_columns
where constraint_name = theCons and owner = theOwner
order by position;
firstCol BOOLEAN := TRUE;
begin
-- For each constraint
FOR cons IN (sel...
How to get the data-id attribute?
...e info here">My Awesome Div</div>
JS
var myDiv = document.querySelector('#my-div');
myDiv.dataset.info // "some info here"
myDiv.dataset.otherInfo // "more info here"
Demo: http://html5demos.com/dataset
Full browser support list: http://caniuse.com/#feat=dataset
...
PostgreSQL ERROR: canceling statement due to conflict with recovery
...is not modified is to suspend the replication and resume after the query:
select pg_xlog_replay_pause(); -- suspend
select * from foo; -- your query
select pg_xlog_replay_resume(); --resume
share
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Picking a random element from a set
... the buckets that make up the hashset, which allows us to more efficiently select a random elements. If random elements are necessary in Java, it might be worthwhile to define a custom hash set that allows the user to look under the hood. See [boost's docs][1] for a little more in this. [1] boos...
What is the difference between Scope_Identity(), Identity(), @@Identity, and Ident_Current()?
...ction is not used to get an identity, it's used to create an identity in a select...into query.
The session is the database connection. The scope is the current query or the current stored procedure.
A situation where the scope_identity() and the @@identity functions differ, is if you have a trig...