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How to find elements by class
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CSS selectors
single class first match
soup.select_one('.stylelistrow')
list of matches
soup.select('.stylelistrow')
compound class (i.e. AND another class)
soup.select_one('.stylelistrow.otherclassname')
soup.select('.st...
How to hide a in a menu with CSS?
...hat Chrome, it seems, will not allow me to hide <option> in a <select> . Firefox will.
13 Answers
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Joining three tables using MySQL
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Simply use:
select s.name "Student", c.name "Course"
from student s, bridge b, course c
where b.sid = s.sid and b.cid = c.cid
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LINQ: Select an object and change some properties without creating a new object
.... But here is the expanded LINQ expression example.
var query = someList.Select(x => { x.SomeProp = "foo"; return x; })
What this does is use an anonymous method vs and expression. This allows you to use several statements in one lambda. So you can combine the two operations of setting the ...
Is it possible to use the SELECT INTO clause with UNION [ALL]?
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This works in SQL Server:
SELECT * INTO tmpFerdeen FROM (
SELECT top 100 *
FROM Customers
UNION All
SELECT top 100 *
FROM CustomerEurope
UNION All
SELECT top 100 *
FROM CustomerAsia
UNION All
SELECT top 100 *
FROM CustomerAme...
How to determine total number of open/active connections in ms sql server 2005
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This shows the number of connections per each DB:
SELECT
DB_NAME(dbid) as DBName,
COUNT(dbid) as NumberOfConnections,
loginame as LoginName
FROM
sys.sysprocesses
WHERE
dbid > 0
GROUP BY
dbid, loginame
And this gives the total:
SELECT
CO...
Retrieve the maximum length of a VARCHAR column in SQL Server
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Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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Difference between SelectedItem, SelectedValue and SelectedValuePath
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Their names can be a bit confusing :). Here's a summary:
The SelectedItem property returns the entire object that your list is bound to. So say you've bound a list to a collection of Category objects (with each Category object having Name and ID properties). eg. ObservableCollection&l...
List of all index & index columns in SQL Server DB
...lumns.
EDIT: This query's getting pretty close to what you're looking for:
SELECT
TableName = t.name,
IndexName = ind.name,
IndexId = ind.index_id,
ColumnId = ic.index_column_id,
ColumnName = col.name,
ind.*,
ic.*,
col.*
FROM
sys.indexes ind
INNER JOI...
SQL RANK() versus ROW_NUMBER()
...he first 3 rows are tied when ordered by ID)
WITH T(StyleID, ID)
AS (SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,2)
SELECT *,
RANK() OVER(PARTITION BY StyleID ORDER BY ID) AS 'RANK',
ROW_NUMBER() OVER(PARTITION BY Style...