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What is a clearfix?
...er list see: https://caniuse.com/flexbox.
(Perhaps once its position is established completely, it may be the absolutely recommended way of laying out elements.)
A clearfix is a way for an element to automatically clear its child elements, so that you don't need to add additional markup. It's ge...
Any good boolean expression simplifiers out there? [closed]
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Note that if you want the truth table, which is not always outputed for some expressions, then start the query with the words "truth table" followed by the expression
– Belgi
May 20 '17 at 13:00
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select and update database record with a single queryset
...ew value based on the old field value that is do something like:
update my_table set field_1 = field_1 + 1 where pk_field = some_value
use query expressions:
MyModel.objects.filter(pk=some_value).update(field1=F('field1') + 1)
This will execute update atomically that is using one update request to...
How to drop columns by name in a data frame
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I tried to delete a column while using the package data.table and got an unexpected result. I kind of think the following might be worth posting. Just a little cautionary note.
[ Edited by Matthew ... ]
DF = read.table(text = "
fruit state grade y1980 y1990 y2000
app...
In Django, how does one filter a QuerySet with dynamic field lookups?
... right. It sounds like the "field" is actually a key to a row in another table, not a column.
Specific filter buttons. Wait... That's the way the Django admin works. Specific filters are turned into buttons. And the same analysis as above applies. A few filters make sense. A large number of ...
Convert character to ASCII code in JavaScript
... en.wikipedia.org/wiki/ASCII - I'm pretty proud the coloring I did for the tables on that page remains there after almost 10 years : )
– B T
Apr 25 '14 at 19:00
9
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How do I escape a single quote in SQL Server?
I'm trying to insert some text data into a table in SQL Server 9.
13 Answers
13
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Getting key with maximum value in dictionary?
...th item>
Returned values will be compared.
Dict
Python dict is a hash table. A key of dict is a hash of an object declared as a key. Due to performance reasons iteration though a dict implemented as iteration through it's keys.
Therefore we can use it to rid operation of obtaining a keys list.
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sql primary key and index
...ou may reach the desired optimization for a query.
For example you have a table with many columns but you are only querying ID, Name and Address columns. Taking ID as the primary key, we can create the following index that is built on ID but includes Name and Address columns.
CREATE NONCLUSTERED I...
What are .dex files in Android?
...lication code file.
Android programs are compiled into .dex (Dalvik Executable) files, which are in turn zipped into a single .apk file on the device. .dex files can be created by automatically translating compiled applications written in the Java programming language.
Dex file format:
1. File ...