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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
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create table test (a int, b int , c int, d int);
alter table test drop column b, d;
Be aware that DROP COLUMN does not physically remove the data, and for fixed length types (int, numeric, float, datetime, uniqueidentifier etc) the spac...
Remove blank attributes from an Object in Javascript
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You can loop through the object:
var test = {
test1 : null,
test2 : 'somestring',
test3 : 3,
}
function clean(obj) {
for (var propName in obj) {
if (obj[propName] === null || obj[propName] === undefined) {
delete obj[propName];
}
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How do I remove the last comma from a string using PHP?
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You can use substr function to remove this.
$t_string = "'test1', 'test2', 'test3',";
echo substr($t_string, 0, -1);
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Copy values from one column to another in the same table
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Short answer for the code in question is:
UPDATE `table` SET test=number
Here table is the table name and it's surrounded by grave accent (aka back-ticks `) as this is MySQL convention to escape keywords (and TABLE is a keyword in that case).
BEWARE, that this is pretty dangerous qu...
How to get error message when ifstream open fails
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Thanks. I didn't test this because strerror(errno) posted in the comments works and very simple for using. I think that e.what will work, since errno works.
– Alex F
Jun 27 '13 at 9:01
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How to disable CSS in Browser for testing purposes
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That's the fastest way to do it, I like that method.
– ling
Sep 24 '16 at 20:56
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Can I have H2 autocreate a schema in an in-memory database?
...could run a script, or just a statement or two:
String url = "jdbc:h2:mem:test;" +
"INIT=CREATE SCHEMA IF NOT EXISTS TEST"
String url = "jdbc:h2:mem:test;" +
"INIT=CREATE SCHEMA IF NOT EXISTS TEST\\;" +
"SET SCHEMA TEST";
String url = "jdbc:h2:mem;" + ...
Django filter queryset __in for *every* item in list
...ries.
You also have the option of using custom queries.
Some examples
Test setup:
class Photo(models.Model):
tags = models.ManyToManyField('Tag')
class Tag(models.Model):
name = models.CharField(max_length=50)
def __unicode__(self):
return self.name
In [2]: t1 = Tag.obje...
Bulk insert with SQLAlchemy ORM
...ree of ORM-based automation.
The example below illustrates time-based tests for several different
methods of inserting rows, going from the most automated to the least.
With cPython 2.7, runtimes observed:
classics-MacBook-Pro:sqlalchemy classic$ python test.py
SQLAlchemy ORM: Total time f...
How to use System.Net.HttpClient to post a complex type?
... code (from dunston) becomes:
Widget widget = new Widget()
widget.Name = "test"
widget.Price = 1;
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("http://localhost:44268");
client.PostAsJsonAsync("api/test", widget)
.ContinueWith((postTask) => postTask.Result.EnsureSucces...