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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...
Restrictions
You can ask the system catalog pg_database - accessible from any database in the same database cluster. The tricky part is that CREATE DATABASE can only be executed as a single statement. The manual:
CREATE DATABASE cannot be executed inside a transaction b...
How to ALTER multiple columns at once in SQL Server
...LE statements.
Try following:
ALTER TABLE tblcommodityOHLC alter column CC_CommodityContractID NUMERIC(18,0);
ALTER TABLE tblcommodityOHLC alter column CM_CommodityID NUMERIC(18,0);
share
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improv...
What is the difference between String.Empty and “” (empty string)?
...private hidebysig instance string foo() cil managed
{
.maxstack 8
L_0000: ldstr "foo"
L_0005: ret
}
.method private hidebysig instance string bar() cil managed
{
.maxstack 8
L_0000: ldstr "bar"
L_0005: ldsfld string [mscorlib]System.String::Empty
L_000a: call string [msc...
Any way to replace characters on Swift String?
...n leaves me with and optional string. Original String looks like this: "x86_64" and the new mapping looks like "Optional([\"x\", \"8\", \"6\", \"_\", \"6\", \"4\"])"
– John Shelley
Oct 19 '15 at 15:07
...
'Java' is not recognized as an internal or external command
...
You need to configure your environment variables, JAVA_HOME and PATH.
JAVA_HOME must contain the path to java, and you should add %JAVA_HOME%\bin to PATH
Alternatively, you can simply add to your PATH the whole path to the bin folder, without the JAVA_HOME variable, however, t...
Schema for a multilanguage database
...ng a related translation table for each translatable table?
CREATE TABLE T_PRODUCT (pr_id int, PRICE NUMBER(18, 2))
CREATE TABLE T_PRODUCT_tr (pr_id INT FK, languagecode varchar, pr_name text, pr_descr text)
This way if you have multiple translatable column it would only require a single join to g...
How does Bluebird's util.toFastProperties function make an object's properties “fast”?
...es it slow.
assertFalse(%HasFastProperties(proto));
DoProtoMagic(proto, set__proto__);
// Making it a prototype makes it fast again.
assertTrue(%HasFastProperties(proto));
Reading and running this test shows us that this optimization indeed works in v8. However - it would be nice to see how.
If we ...
Asp.NET Web API - 405 - HTTP verb used to access this page is not allowed - how to set handler mappi
...bling doesn't help, you have to un-install it.
– John_
May 10 '12 at 16:08
I can confirm that disabling doesn't help. ...
How to set Python's default version to 3.x on OS X?
...on='python3'
in your ~/.profile, and then source ~/.profile in your ~/.bash_profile and/or your~/.zsh_profile with a line like:
[ -e ~/.profile ] && . ~/.profile
This way, your alias will work across shells.
With this, python command now invokes python3. If you want to invoke the "origi...
What are the advantages of NumPy over regular Python lists?
...nts = 10000
Ntimeits = 10000
x = arange(Nelements)
y = range(Nelements)
t_numpy = Timer("x.sum()", "from __main__ import x")
t_list = Timer("sum(y)", "from __main__ import y")
print("numpy: %.3e" % (t_numpy.timeit(Ntimeits)/Ntimeits,))
print("list: %.3e" % (t_list.timeit(Ntimeits)/Ntimeits,))
w...