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Difference between save and saveAndFlush in Spring data jpa
... flush mode AUTO and you are using your application to first save and then select the data again, you will not see a difference in bahvior between save() and saveAndFlush() because the select triggers a flush first. See the documention.
...
difference between primary key and unique key
...ey, unique key, etc are collectively called as Candidate Key.
However, DBA selected a key from candidate key for searching records is called Primary key.
Difference between Primary Key and Unique key
1. Behavior: Primary Key is used to identify a row (record) in a table, whereas Unique-key is to...
Why should I use core.autocrlf=true in Git?
I have a Git repository that is accessed from both Windows and OS X, and that I know already contains some files with CRLF line-endings. As far as I can tell, there are two ways to deal with this:
...
Loop through files in a folder using VBA?
...2 Then
FileExtStr = ".xls": FileFormatNum = -4143
Else
Select Case xWb.FileFormat
Case 51:
FileExtStr = ".xlsx": FileFormatNum = 51
Case 52:
If Application.ActiveWorkbook.HasVBProject Then
FileExtStr = "....
How do I use IValidatableObject?
...ustom model binder):
var resultsGroupedByMembers = validationResults
.SelectMany(vr => vr.MemberNames
.Select(mn => new { MemberName = mn ?? "",
Error = vr.ErrorMessage }))
.GroupBy(x => x.MemberName);
foreach (v...
HQL ERROR: Path expected for join
...
select u from UserGroup ug inner join ug.user u
where ug.group_id = :groupId
order by u.lastname
As a named query:
@NamedQuery(
name = "User.findByGroupId",
query =
"SELECT u FROM UserGroup ug " +
"INNER JOIN...
Should CSS always preceed Javascript?
...ownload each time a page is loaded.
To simulate reality, I included jQuery and the H5BP CSS (so there's a decent amount of script/CSS to parse)
Set up two pages - one with CSS before script, one with CSS after script.
Recorded how long it took for the external script in the <head> to execute
R...
How to query as GROUP BY in django?
...nnotate(dcount=Count('designation'))
This results in a query similar to
SELECT designation, COUNT(designation) AS dcount
FROM members GROUP BY designation
and the output would be of the form
[{'designation': 'Salesman', 'dcount': 2},
{'designation': 'Manager', 'dcount': 2}]
...
How do I create a simple 'Hello World' module in Magento?
...ck our work). In the admin application
Go to System->Cache Management
Select Refresh from the All Cache menu
Click Save Cache settings
Now, we make sure that Magento knows about the module
Go to System->Configuration
Click Advanced
In the "Disable modules output" setting box, look for yo...
Parsing huge logfiles in Node.js - read in line-by-line
...
'line-by-line' is more memory efficient than the selected answer. For 1 million lines in a csv the selected answer had my node process in the low 800s of megabytes. Using 'line-by-line' it was consistently in the low 700s. This module also keeps the code clean and easy to r...