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How can I check if a View exists in a Database?
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If you found this to decide between a CREATE and ALTER for a view (as I did), this doesn't work for VIEWs - you have to DROP the VIEW* and then CREATE it. The IF EXISTS still works fine for DROPing the VIEW tho, so thanks! :) * Don't forget about any permissions when y...
What's the difference between belongs_to and has_one?
What is the difference between a belongs_to and a has_one ?
5 Answers
5
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Update multiple columns in SQL
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The "tiresome way" is standard SQL and how mainstream RDBMS do it.
With a 100+ columns, you mostly likely have a design problem... also, there are mitigating methods in client tools (eg generation UPDATE statements) or by using ORMs
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How to add images in select list?
...others</option>
</select>
Better yet, you can separate HTML and CSS like that
HTML
<select id="gender">
<option>male</option>
<option>female</option>
<option>others</option>
</select>
CSS
select#gender option[value="male"] ...
Easiest way to compare arrays in C#
...in array or tuples via using StructuralComparisons type:
object[] a1 = { "string", 123, true };
object[] a2 = { "string", 123, true };
Console.WriteLine (a1 == a2); // False (because arrays is reference types)
Console.WriteLine (a1.Equals (a2)); // False (because arrays is reference types)...
Primary key or Unique index?
At work we have a big database with unique indexes instead of primary keys and all works fine.
15 Answers
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A connection was successfully established with the server, but then an error occurred during the pre
...e same problem, I was storing session data in the database, the connection string had Encrypt=True in it, which I assume told the sql client to connect to the server in secure (SSL) mode, removing this helped!
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Java: how can I split an ArrayList in multiple small ArrayLists?
... + chunkSize));
}
return chunkList;
}
Eg :
List<Integer> stringList = new ArrayList<>();
stringList.add(0);
stringList.add(1);
stringList.add(2);
stringList.add(3);
stringList.add(4);
stringList.add(5);
stringList.add(6);
stringList.add(7);
stringList.add(8);
stringList.add(9...
jQuery Event Keypress: Which key was pressed?
...ome other way to get rid of these magic numbers.
You can also make use of String.charCodeAt and .fromCharCode:
>>> String.charCodeAt('\r') == 13
true
>>> String.fromCharCode(13) == '\r'
true
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Exit single-user mode
Currently, my database is in Single User mode. When I try to expand me database, I get an error:
18 Answers
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