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How can I return pivot table output in MySQL?
...OUP BY.
The basic SQL providing this pivot can look something like this:
SELECT P.`company_name`,
COUNT(
CASE
WHEN P.`action`='EMAIL'
THEN 1
ELSE NULL
END
) AS 'EMAIL',
COUNT(
CASE
WHEN P.`action`='PRINT' AND...
SQL Joins Vs SQL Subqueries (Performance)?
...e result i was looking for was 739 elements.
My query at first was this:
SELECT p.id,
p.fixedId,
p.azienda_id,
p.categoria_id,
p.linea,
p.tipo,
p.nome
FROM prodotto p
WHERE p.azienda_id = 2699 AND p.anno = (
SELECT MAX(p2.anno)
FROM prodotto p2
WHERE p2.fixed...
Can you use an alias in the WHERE clause in mysql?
...ts an unknown column. Is there any way to get around this issue? I need to select records that have a rating higher than x. Rating is calculated as the following alias:
...
Making macOS Installer Packages which are Developer ID ready
...gbuild
persisting obsolescence
Known Issues and Workarounds
Destination Select Pane
The user is presented with the destination select option with only a single choice - "Install for all users of this computer". The option appears visually selected, but the user needs to click on it in order to p...
Use LINQ to get items in one List, that are not in another List
...erride the equality:
var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));
This variant does not remove duplicates.
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postgresql COUNT(DISTINCT …) very slow
...
You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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Modifying a subset of rows in a pandas dataframe
...The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, 'B'] = df.loc[df.A==0, 'B'] / 2
I don't know enough about pandas internals to know exactly why that works, but the basic is...
How do I use jQuery's form.serialize but exclude empty fields
... looking over the jQuery docs and I think we can do this in one line using selectors:
$("#myForm :input[value!='']").serialize() // does the job!
Obviously #myForm gets the element with id "myForm" but what was less obvious to me at first was that the space character is needed between #myForm and...
Indentation shortcuts in Visual Studio
I'm new to Visual Studio 2010 and C#. How can I indent the selected text to left/right by using shortcuts?
8 Answers
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How do I get a distinct, ordered list of names from a DataTable using LINQ?
...tainable, you can also split it up into multiple LINQ statements.
First, select your data into a new list, let's call it x1, do a projection if desired
Next, create a distinct list, from x1 into x2, using whatever distinction you require
Finally, create an ordered list, from x2 into x3, sorting by...