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The JPA hashCode() / equals() dilemma
...Read this very nice article on the subject: Don't Let Hibernate Steal Your Identity.
The conclusion of the article goes like this:
Object identity is deceptively hard to implement correctly when
objects are persisted to a database. However, the problems stem
entirely from allowing objects t...
Clicking the text to select corresponding radio button
...you've got a label on the form itself. You want to put labels on each individual radio group, as shown below.
<form>
<p>What is my middle name?</p>
<br>
<input id="349" type="radio" value="1" name="question1">
<label for="349">Abe</label>
...
A migration to add unique constraint to a combination of columns
...
The problem with the model level validation is that it doesn't scale. Two servers could run the same data through at the same time (like a double tap on an api heavy app) I have two identical records in my DB right now and the model has the validation..
...
Drop a temporary table if it exists
... IF EXISTS ##CLIENTS_KEYWORD
On previous versions you can use
IF OBJECT_ID('tempdb..##CLIENTS_KEYWORD', 'U') IS NOT NULL
/*Then it exists*/
DROP TABLE ##CLIENTS_KEYWORD
CREATE TABLE ##CLIENTS_KEYWORD
(
client_id INT
)
You could also consider truncating the table instead rather than dropping ...
How to get WordPress post featured image URL
...t me know if it works for you.
<?php if (has_post_thumbnail( $post->ID ) ): ?>
<?php $image = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'single-post-thumbnail' ); ?>
<div id="custom-bg" style="background-image: url('<?php echo $image[0]; ?>')"&g...
What is more efficient? Using pow to square or just multiply it with itself?
...i*i*i: 9.7e-05s (result = 2.5e+07)
So it looks like the compiler does at least try to optimise the std::pow(x,2) case, but not the std::pow(x,3) case (it takes ~40 times longer than the std::pow(x,2) case). In all cases, manual expansion performed better - but particularly for the power 3 case (60...
View/edit ID3 data for MP3 files
What's a quick and easy way to view and edit ID3 tags (artist, album, etc.) using C#?
6 Answers
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Rails auto-assigning id that already exists
...
Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
SELECT setval('company_id_seq', (SELECT max(...
Django database query: How to get object by id?
Django automatically creates an id field as primary key.
6 Answers
6
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Delete duplicate records in SQL Server?
Consider a column named EmployeeName table Employee . The goal is to delete repeated records, based on the EmployeeName field.
...