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select count(*) from table of mysql in php

... to alias the aggregate using the as keyword in order to call it from mysql_fetch_assoc $result=mysql_query("SELECT count(*) as total from Students"); $data=mysql_fetch_assoc($result); echo $data['total']; share |...
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How to join (merge) data frames (inner, outer, left, right)

...nner join: merge(df1, df2) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(df1, df2, by = "CustomerId") to make sure that you were matching on only the fields you desired. You can also use the by.x and b...
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Calling a class function inside of __init__

... Call the function in this way: self.parse_file() You also need to define your parse_file() function like this: def parse_file(self): The parse_file method has to be bound to an object upon calling it (because it's not a ...
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Best practices for catching and re-throwing .NET exceptions

... that bombs here } catch (Exception ex) { throw; } throw ex; is basically like throwing an exception from that point, so the stack trace would only go to where you are issuing the throw ex; statement. Mike is also correct, assuming the exception allows you to pass an exception (which is recom...
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Draw text in OpenGL ES

I'm currently developing a small OpenGL game for the Android platform and I wonder if there's an easy way to render text on top of the rendered frame (like a HUD with the player´s score etc). The text would need to use a custom font also. ...
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How to [recursively] Zip a directory in PHP?

...ce), file_get_contents($source)); } return $zip->close(); } Call it like this: Zip('/folder/to/compress/', './compressed.zip'); share | improve this answer | ...
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UITableViewCell, show delete button on swipe

... During startup in (-viewDidLoad or in storyboard) do: self.tableView.allowsMultipleSelectionDuringEditing = NO; Override to support conditional editing of the table view. This only needs to be implemented if you are going to be returning NO for some items. By default, all items are editable....
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The model used to open the store is incompatible with the one used to create the store

...el select your new version of data model for current data model THAT'S NOT ALL ) You should perform so called "light migration". Go to your AppDelegate and find where the persistentStoreCoordinator is being created Find this line if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteS...
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How do you serialize a model instance in Django?

... You can easily use a list to wrap the required object and that's all what django serializers need to correctly serialize it, eg.: from django.core import serializers # assuming obj is a model instance serialized_obj = serializers.serialize('json', [ obj, ]) ...
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ViewPager and fragments — what's the right way to store fragment's state?

...agment will be placed. FragmentPagerAdapter.getItem(int position) is only called when a fragment for that position does not exist. After rotating, Android will notice that it already created/saved a fragment for this particular position and so it simply tries to reconnect with it with FragmentManage...