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How to speed up insertion performance in PostgreSQL
...rypto module) is (a lot) faster than uuid_generate_v4()
=# explain analyze select uuid_generate_v4(),* from generate_series(1,10000);
QUERY PLAN
---------------------------------------------------------------------------------------------------...
Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine
...Engine 2010 and force your .NET application to run in 32-bit mode (e.g. by selecting x86 platform in Configuration Manager). And the proper solution is to replace MS Access with a better alternative.
– Massood Khaari
Sep 25 '13 at 5:26
...
Submitting HTML form using Jquery AJAX
...ral web actions GET, POST, PUT, and DELETE; these directly correspond with SELECT/Retreiving DATA, INSERTING DATA, UPDATING/UPSERTING DATA, and DELETING DATA. A default HTML/ASP.Net webform/PHP/Python or any other form action is to "submit" which is a POST action. Because of this the below will al...
Improve INSERT-per-second performance of SQLite
...ple threads (connection per-thread).
First find the items, in the table:
SELECT COUNT(*) FROM table
then read in pages (LIMIT/OFFSET):
SELECT * FROM table ORDER BY _ROWID_ LIMIT <limit> OFFSET <offset>
where and are calculated per-thread, like this:
int limit = (count + n_threa...
How to combine two or more querysets in a Django view?
...s. For example:
>>> qs1.union(qs2, qs3)
The UNION operator selects only distinct values by default. To allow duplicate values, use the all=True
argument.
union(), intersection(), and difference() return model instances of
the type of the first QuerySet even if the arguments ...
How to enter a multi-line command
...e grave accent (backtick):
Get-ChildItem -Recurse `
-Filter *.jpg `
| Select LastWriteTime
However, this is only ever necessary in such cases as shown above. Usually you get automatic line continuation when a command cannot syntactically be complete at that point. This includes starting a new...
How to call an async method from a getter or setter?
...
You can use Task like this :
public int SelectedTab
{
get => selected_tab;
set
{
selected_tab = value;
new Task(async () =>
{
await newTab.ScaleTo...
Using TortoiseSVN how do I merge changes from the trunk to a branch and vice versa?
...rge Type: Merge a range of revisions | Click 'Next'
Merge revision range: Select the URL of the trunk directory that you copied to the branch / tag. Enter the revisions to merge or leave the field empty to merge all revisions | click 'Next'
Merge options: I just left these as default | click 'Merg...
How to remove unused imports from Eclipse
...rences → Java → Editor → Save Actions.
Check the option "Perform the selected actions on save".
Check the option "Organize imports".
Now every time you save your classes, eclipse will take care of removing the unused imports.
...
INNER JOIN vs LEFT JOIN performance in SQL Server
...(ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')
SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name
SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name
DROP TABLE #Test1
DROP TABLE #Test2
If you run this and view the execution plan, you'll se...