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Migration: Cannot add foreign key constraint
I'm trying to create foreign keys in Laravel however when I migrate my table using artisan i am thrown the following error:
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Remove by _id in MongoDB console
In the MongoDB console how can I remove a record by id? Here's my collection :
11 Answers
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How can I generate a unique ID in Python? [duplicate]
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Perhaps uuid.uuid4() might do the job. See uuid for more information.
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Can I use CASE statement in a JOIN condition?
The following image is a part of Microsoft SQL Server 2008 R2 System Views. From the image we can see that the relationship between sys.partitions and sys.allocation_units depends on the value of sys.allocation_units.type . So to join them together I would write something similar to this:
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How do I search for an object by its ObjectId in the mongo console?
I've found this question answered for C# and Perl, but not in the native interface. I thought this would work:
12 Answers
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Query to list number of records in each table in a database
How to list row count of each table in the database. Some equivalent of
21 Answers
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How to do a FULL OUTER JOIN in MySQL?
I want to do a Full Outer Join in MySQL. Is this possible? Is a Full Outer Join supported by MySQL?
15 Answers
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Showing empty view when ListView is empty
For some reason the empty view, a TextView in this case, always appears even when the ListView is not empty. I thought the ListView would automatically detect when to show the empty view.
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Android OnClickListener - identify a button
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You will learn the way to do it, in an easy way, is:
public class Mtest extends Activity {
Button b1;
Button b2;
public void onCreate(Bundle savedInstanceState) {
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b1 = (Button) findViewById(R.id.b1);
b2 = (Button) findViewById(R.id.b2)...
Real life example, when to use OUTER / CROSS APPLY in SQL
I have been looking at CROSS / OUTER APPLY with a colleague and we're struggling to find real life examples of where to use them.
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