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Difference between View and table in sql
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A table contains data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database).
The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database w...
add column to mysql table if it does not exist
...rade_database_1_0_to_2_0()
BEGIN
-- rename a table safely
IF NOT EXISTS( (SELECT * FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=DATABASE()
AND TABLE_NAME='my_old_table_name') ) THEN
RENAME TABLE
my_old_table_name TO my_new_table_name,
END IF;
-- add a column safely
IF NO...
Visual Studio hot keys change occasionally, specifically F6 vs Ctrl-Shift-B for building. WHY?
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This is because you might have selected "General Development Settings" as your default environment settings for your Visual Studio (which usually we do on the first launch of VS after installing it as it pops up a dialogue box to choose default environment...
How do I clear all options in a dropdown box?
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You can use the following to clear all the elements.
var select = document.getElementById("DropList");
var length = select.options.length;
for (i = length-1; i >= 0; i--) {
select.options[i] = null;
}
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Is there any kind of hash code function in JavaScript?
... var hash = 0;
for (var i = 0; i < this.length; i++) {
var character = this.charCodeAt(i);
hash = ((hash<<5)-hash)+character;
hash = hash & hash; // Convert to 32bit integer
}
return hash;
}
That is the way of implementation in Java (bitwise operat...
Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
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ERROR ITMS-9000: “Redundant Binary Upload. There already exists a binary upload with build version '
...umber just has to be unique (and higher) for each binary that is uploaded (select the Target, then Xcode -> General -> Build, see the picture below).
For example in the image below the build uploaded has version 3.1.4 (3.75 in the older image) and the build number is 1. Thus, after uploading t...
Where is the “Create Unit Tests” selection?
..."Show commands containing" text box to filter out CreateUnitTests command, select it. Choose "Text Editor" in "Use new shortcut in" combo, and press shortcut you want in "Press shortcut keys" text field (e.g., Ctrl+T, Ctrl+C). Finally, press Assign button. Enjoy!
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Select elements by attribute
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Do you mean can you select them? If so, then yes:
$(":checkbox[myattr]")
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Open file dialog and select a file using WPF controls and C#
...y files to search only for image files (type jpg, png, bmp...).
And when I select an image file and click Ok in the file dialog I want the file directory to be written in the textbox1.text like this:
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