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Using DISTINCT and COUNT together in a MySQL Query
...ion better passing two params to COUNT( ).
– Rockin4Life33
Aug 1 '18 at 18:23
To my surprise, I found that there canno...
How to select option in drop down using Capybara
...
If you take a look at the source of the select method, you can see that what it does when you pass a from key is essentially:
find(:select, from, options).find(:option, value, options).select_option
In other words, it find...
How is the “greater than” or “>” character used in CSS?
...to be able to style the content of
elements contained within other
specified elements. For example,
suppose one wants to set white as the
color of hyperlinks inside of div tags
for a certain class because they have
a dark background. This can be
accomplished by using a period to
comb...
Setting DEBUG = False causes 500 Error
... need to add:
# Hosts/domain names that are valid for this site; required if DEBUG is False
# See https://docs.djangoproject.com/en/1.9/ref/settings/#allowed-hosts
ALLOWED_HOSTS = []
Add your host here like ['www.beta800.net'] or ['*'] for a quick test, but don't use ['*'] for production.
...
What's the use of do while(0) when we define a macro? [duplicate]
...emicolon and make it look and act more like a function.
It also works with if/else clauses properly then.
Without the while(0), your code above would not work with
if (doit)
INIT_LIST_HEAD(x);
else
displayError(x);
since the semicolon after the macro would "eat" the else clause, and the...
CREATE TABLE IF NOT EXISTS equivalent in SQL Server [duplicate]
CREATE TABLE IF NOT EXISTS works on mysql but fails with SQL Server 2008 R2.
What is the equivalent syntax?
1 Answer
...
Python 'If not' syntax [duplicate]
I'm a bit confused about how/why so many python developers use if not in their conditional statements.
1 Answer
...
Preview layout with merge root tag in Intellij IDEA/Android Studio
...tTag tools attribute (added in Android Studio 2.2) that you can use to specify the layout type for a merge tag, which will make the layout render correctly in the layout editor preview.
So using your example:
<merge xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="ht...
Recommended way to insert elements into map [duplicate]
... is not a recommended way - it is one of the ways to insert into map. The difference with operator[] is that the insert can tell whether the element is inserted into the map. Also, if your class has no default constructor, you are forced to use insert.
operator[] needs the default constructor be...
Android Debug Bridge (adb) device - no permissions [duplicate]
...4df15d6e02a55f15 device
???????????? no permissions
Investigation
If I run lsusb, I can see which devices I have connected, and where:
$ lsusb
...
Bus 002 Device 050: ID 04e8:6860 Samsung Electronics Co., Ltd GT-I9100 Phone ...
Bus 002 Device 049: ID 18d1:4e42 Google Inc.
This is showin...