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Reset auto increment counter in postgres
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If you created the table product with an id column, then the sequence is not simply called product, but rather product_id_seq (that is, ${table}_${column}_seq).
This is the ALTER SEQUENCE command you need:
ALTER SEQUENCE pr...
Center Align on a Absolutely Positioned Div
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Your problem may be solved if you give your div a fixed width, as follows:
div#thing {
position: absolute;
top: 0px;
z-index: 2;
width:400px;
margin-left:-200px;
left:50%;
}
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How to check if a json key exists?
So, I get some JSON values from the server but I don't know if there will be a particular field or not.
13 Answers
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Are negative array indexes allowed in C?
...ubtracted from a pointer, the result has the type of the pointer operand. If the pointer operand points to an element of an array object, and the array is large enough, the result points to an element offset from the original element such that the difference of the subscripts of the resulting and o...
SQL order string as number
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If possible you should change the data type of the column to a number if you only store numbers anyway.
If you can't do that then cast your column value to an integer explicitly with
select col from yourtable
order by cast...
How to convert char to int?
... ParseInt32(this char value) {
int i = (int)(value - '0');
if (i < 0 || i > 9) throw new ArgumentOutOfRangeException("value");
return i;
}
}
then use int x = c.ParseInt32();
share
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Can table columns with a Foreign Key be NULL?
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@CJDennis If you make it so that only one row can have a null ID, it could be used as fallback values for other rows. (Though it might work out better for the DB if you just use more columns.) The default constraint seems like a proble...
ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
...Changed;
}
public void ContentCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
//This will get called when the collection is changed
}
}
Okay, that's twice today I've been bitten by the MSDN documentation being wrong. In the link I gave you it says:...
Representing null in JSON
...hat is the preferred method for returning null values in JSON? Is there a different preference for primitives?
7 Answers
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Capture HTML Canvas as gif/jpg/png/pdf?
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Oops. Original answer was specific to a similar question. This has been revised:
var canvas = document.getElementById("mycanvas");
var img = canvas.toDataURL("image/png");
with the value in IMG you can write it out as a new Image like so:
document...