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How to select html nodes by ID with jquery when the id contains a dot?
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@Tomalak in comments:
since ID selectors must be preceded by a hash #, there should be no ambiguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The correct...
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:
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postgresql COUNT(DISTINCT …) very slow
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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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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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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...
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...
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...
MySQL: Transactions vs Locking Tables
...ransactions vs locking tables to ensure database integrity and make sure a SELECT and UPDATE remain in sync and no other connection interferes with it. I need to:
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Freezing Row 1 and Column A at the same time
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Select cell B2 and click "Freeze Panes" this will freeze Row 1 and Column A.
For future reference, selecting Freeze Panes in Excel will freeze the rows above your selected cell and the columns to the left of your selected ce...