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Add new column with foreign key constraint in one command
I am trying to add a new column that will be a foreign key. I have been able to add the column and the foreign key constraint using two separate ALTER TABLE commands:
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PHP - Extracting a property from an array of objects
...here are 2 solutions:
First (Newer PHP versions)
As @JosepAlsina said before the best and also shortest solution is to use array_column as following:
$catIds = array_column($objects, 'id');
Notice:
For iterating an array containing \stdClasses as used in the question it is only possible with P...
SELECT * FROM X WHERE id IN (…) with Dapper ORM
...y to write a query with IN clause using Dapper ORM when the list of values for the IN clause is coming from business logic? For example let's say I have a query:
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Why does MYSQL higher LIMIT offset slow the query down?
...able t
ON t.id = q.id
See this article:
MySQL ORDER BY / LIMIT performance: late row lookups
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Mysql error 1452 - Cannot add or update a child row: a foreign key constraint fails
I'm having a bit of a strange problem. I'm trying to add a foreign key to one table that references another, but it is failing for some reason. With my limited knowledge of MySQL, the only thing that could possibly be suspect is that there is a foreign key on a different table referencing the one I ...
What does “for” attribute do in HTML tag?
...='theinput' id='theinput'>
</label>
The other way is to use the for attribute, giving it the ID of the associated input:
<label for="theinput">Input here:</label>
<input type='text' name='whatever' id='theinput'>
This is especially useful for use with checkboxes and b...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...the three options, the LEFT JOIN/IS NULL is less efficient. See this link for more details.
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How do I perform the SQL Join equivalent in MongoDB?
How do I perform the SQL Join equivalent in MongoDB?
19 Answers
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Defining a percentage width for a LinearLayout? [duplicate]
I want to define a percentage width (70%) for a LinearLayout that contains some buttons, so that I can center it and so that the child buttons can fill_parent. Here's a picture showing what I mean:
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Is there a download function in jsFiddle?
... with the CSS, HTML and JS in one file, so you can run it without jsFiddle for debug purposes?
16 Answers
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