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How to add a primary key to a MySQL table?
... Column
If you want to add a primary key constraint to an existing column all of the previously listed syntax will fail.
To add a primary key constraint to an existing column use the form:
ALTER TABLE `goods`
MODIFY COLUMN `id` INT(10) UNSIGNED PRIMARY KEY AUTO_INCREMENT;
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Should I call Close() or Dispose() for stream objects?
... StreamWriter etc implements IDisposable interface. That means, we can call Dispose() method on objects of these classes. They've also defined a public method called Close() . Now that confuses me, as to what should I call once I'm done with objects? What if I call both?
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Remove blank lines with grep
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Try the following:
grep -v -e '^$' foo.txt
The -e option allows regex patterns for matching.
The single quotes around ^$ makes it work for Cshell. Other shells will be happy with either single or double quotes.
UPDATE: This works for me for a file with blank lines or "all white ...
Calculate text width with JavaScript
...ia css selection rules that you may not be cognizant of at the time. Strip all relevant styles from the container before applying the ones you care about before measuring.
– Jason Bunting
Sep 23 '08 at 0:33
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Rotating videos with FFmpeg
...ine).
Note that this will re-encode the audio and video parts. You can usually copy the audio without touching it, by using -c:a copy. To change the video quality, set the bitrate (for example with -b:v 1M) or have a look at the H.264 encoding guide if you want VBR options.
A solution is also to u...
Why doesn't c++ have &&= or ||= for booleans?
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all the more reason to have &&= in my opinion. =P
– Kache
Mar 21 '10 at 20:19
4
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List tables in a PostgreSQL schema
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In all schemas:
=> \dt *.*
In a particular schema:
=> \dt public.*
It is possible to use regular expressions with some restrictions
\dt (public|s).(s|t)
List of relations
Schema | Name | Type | Owner
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Array Size (Length) in C#
...ts out in the comments, there is a concept of a "jagged array", which is really nothing more than a single-dimensional array of (typically single-dimensional) arrays.
For example, one could have the following:
int[][] c = new int[3][];
c[0] = new int[] {1, 2, 3};
c[1] = new int[] {3, 14};
c[2] = ...
Measure the time it takes to execute a t-sql query
... for testing and it takes way too long to run. I canceled at 7 minutes and all the timers added up was only about 2 minutes. So I think there is some return text cache issue or maybe it takes too long to calculate all the datediffs for so many.
– M H
Apr 29 '16...
Load a UIView from nib in Swift
...ere is no need to assign anything to "self". As soon as the XIB is loaded, all outlets are connected, including the top level view. The only thing missing, is to add the top view to the view hierarchy:
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class SomeView: UIView {
required init(coder aDecoder: NSCoder) {
super.init(coder: ...