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PostgreSQL create table if not exists
...ns, here is a function to work around it:
CREATE OR REPLACE FUNCTION create_mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT FROM pg_catalog.pg_tables
WHERE schemaname = 'myschema'
AND tablename = 'mytable') THEN
RAISE NOTICE 'T...
How can I redirect HTTP requests made from an iPad?
....
sudo apt-get install libapache2-mod-proxy-html
sudo a2enmod proxy proxy_http proxy_html
sudo apache2ctl graceful
Then create a virtual host file, for example /etc/apache2/sites-available/my-proxy
Listen *:8080
<VirtualHost *:8080>
ProxyRequests On
<Proxy *>
Order ...
Append to a file in Go
...
This answers works in Go1:
f, err := os.OpenFile(filename, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
if err != nil {
panic(err)
}
defer f.Close()
if _, err = f.WriteString(text); err != nil {
panic(err)
}
...
What are the precise rules for when you can omit parenthesis, dots, braces, = (functions), etc.?
...an use infix with multiple parameters:
string substring (start, end) map (_ toInt) mkString ("<", ", ", ">")
Curried functions are hard to use with infix notation. The folding functions are a clear example of that:
(0 /: list) ((cnt, string) => cnt + string.size)
(list foldLeft 0) ((cnt...
Check if table exists and if it doesn't exist, create it in SQL Server 2008
...omething like this
IF NOT EXISTS (SELECT * FROM sys.objects
WHERE object_id = OBJECT_ID(N'[dbo].[YourTable]') AND type in (N'U'))
BEGIN
CREATE TABLE [dbo].[YourTable](
....
....
....
)
END
share
|...
What's the difference between the data structure Tree and Graph?
...nique for unrooted trees, but that is immaterial.
– j_random_hacker
Jul 7 '14 at 9:42
2
Not quite...
How to make a class conform to a protocol in Swift?
...ataSource : NSObject, UITableViewDataSource {
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "reuseIdentifier", for: indexPath)
// Configure the cell...
...
Java: int array initializes with nonzero elements
...bug will be fixed.
There is only advice at the moment: do not use JDK1.7.0_04 or later if you depend on JLS for newly declared arrays.
Update at October 5:
In the new Build 10 of the JDK 7u10 (early access) released at October 04, 2012, this bug was fixed at least for Linux OS (I did not test for...
Line continuation for list comprehensions or generator expressions in python
...so you can pretty much do as you please. I'd personally prefer
[something_that_is_pretty_long
for something_that_is_pretty_long
in somethings_that_are_pretty_long]
The reason why \ isn't appreciated very much is that it appears at the end of a line, where it either doesn't stand out or needs...
Why does one use dependency injection?
...ime.Now; }}
}
public class OfferWeasel
{
private readonly IGotTheTime _time;
public OfferWeasel(IGotTheTime time)
{
_time = time;
}
public Offer Create(Formdata formdata)
{
var offer = new Offer();
offer.LastUpdated = _time.Now;
return offer...