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When to use EntityManager.find() vs EntityManager.getReference() with JPA
... }
}
If i call find method, JPA provider, behind the scenes, will call
SELECT NAME, AGE FROM PERSON WHERE PERSON_ID = ?
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
If i call getReference method, JPA provider, behind the scenes, will call
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
And ...
Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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How do I select elements of an array given condition?
... x = [5, 2, 3, 1, 4, 5] , y = ['f', 'o', 'o', 'b', 'a', 'r'] . I want to select the elements in y corresponding to elements in x that are greater than 1 and less than 5.
...
Copy a table from one database to another in Postgres
... follow these steps:
In pgAdmin, right click the table you want to move, select "Backup"
Pick the directory for the output file and set Format to "plain"
Click the "Dump Options #1" tab, check "Only data" or "only Schema" (depending on what you are doing)
Under the Queries section, click "Use Colu...
Change name of iPhone app in Xcode 4
...veryone:
1.In the project contents pane at left, click the Folder icon.
2.Select the top-level blue line representing the project.
3.If you don't have the Inspector pane (right pane) open, click the button to enable it. This is the third button in the "View" toolbar towards the upper right corner...
How can I use the $index inside a ng-repeat to enable a class and show a DIV?
...
The issue here is that ng-repeat creates its own scope, so when you do selected=$index it creates a new a selected property in that scope rather than altering the existing one. To fix this you have two options:
Change the selected property to a non-primitive (ie object or array, which makes jav...
How do I reset a sequence in Oracle?
...q_name in varchar2 )
is
l_val number;
begin
execute immediate
'select ' || p_seq_name || '.nextval from dual' INTO l_val;
execute immediate
'alter sequence ' || p_seq_name || ' increment by -' || l_val ||
' minvalue 0';
...
No identities were available - administrator request
...uble click) the new provisioning profile.
In your project's build settings select the NEW provisioning profile (it might have the same name as the old one)
In your project's build settings update your code signing identities (all of them) to the new one if there is one. (The old one was probably exp...
How to group time by hour or by 10 minutes
...time intervals. (There is no collision between years.)
Including it in the SELECT statement will give your output a column with pretty output truncated at the level you specify.
'2000' is an "anchor date" around which SQL will perform the date math. Jereonh discovered below that you encounter an in...
Transferring an app to another Firebase account
...another account. All you have to do is:
Go to your Firebase console, and select the project you want to shift.
Select the cog icon besides the project name on top right.
Select Permissions from the flyout.
Select Advanced permission settings hyperlink.
You've reached the IAM & Admin page of Fi...