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Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
Get full path of the files in PowerShell
...
Add | select FullName to the end of your line above. If you need to actually do something with that afterwards, you might have to pipe it into a foreach loop, like so:
get-childitem "C:\windows\System32" -recurse | where {$_.exte...
Random record in ActiveRecord
...he first, all after are still sorted by id). If you need multiple randomly selected records you must use this approach multiple times or use the random order method provided by your database, i.e. Thing.order("RANDOM()").limit(100) for 100 randomly selected entries. (Be aware that it's RANDOM() in P...
Android Studio doesn't see device
..., follow these steps:
1. go to Run
2. Click on Edit Configurations
3. Select the project
4. find the Target Device section under the General tab on the Android Application page.
That seems to be where you toggle what the project builds to. If you're importing a project it actually defaults t...
iphone: Where the .dSYM file is located in crash report
...
You can locate .dSYM and application binary file in archive.
Select Window -> Organizer
This will open up Organizer window containing last created Archive of project
Right click on Archive and select 'Show in Finder'
Select 'Show Package Content' for archive
Project.xcarchive...
How to take column-slices of dataframe in pandas
...e .loc
See the deprecation in the docs
.loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz, ant, cat, ...
Select between two dates with Django
I am looking to make a query that selects between dates with Django.
4 Answers
4
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How do I rename a column in a SQLite database table?
...lite.org/images/syntax/alter-table-stmt.gif
Example:
CREATE TABLE tab AS SELECT 1 AS c;
SELECT * FROM tab;
ALTER TABLE tab RENAME COLUMN c to c_new;
SELECT * FROM tab;
db-fiddle.com demo
Android Support
As of writing, Android's API 27 is using SQLite package version 3.19.
Based on the cu...
Producing a new line in XSLT
...aps in csv) you can output something like the following:
<xsl:value-of select="concat(elem1,elem2,elem3,$newline)" />
I've used this technique when outputting sql from xml input. In fact, I tend to create variables for commas, quotes and newlines.
...
How can i query for null values in entity framework?
...try in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entry.something == value)
select entry;
This is a nasty b...