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What is :: (double colon) in Python when subscripting sequences?
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TL;DR
This visual example will show you how to a neatly select elements in a NumPy Matrix (2 dimensional array) in a pretty entertaining way (I promise). Step 2 below illustrate the usage of that "double colons" :: in question.
(Caution: this is a NumPy array specific example with...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
Oracle SQL Query for listing all Schemas in a DB
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Using sqlplus
sqlplus / as sysdba
run:
SELECT *
FROM dba_users
Should you only want the usernames do the following:
SELECT username
FROM dba_users
share
|
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How to remove all namespaces from XML with C#?
... return new XElement(xmlDocument.Name.LocalName, xmlDocument.Elements().Select(el => RemoveAllNamespaces(el)));
}
It's working 100%, but I have not tested it much so it may not cover some special cases... But it is good base to start.
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Dynamic Sorting within SQL Stored Procedures
...eing duplicated twice in the order by, and is a little more readable IMO:
SELECT
s.*
FROM
(SELECT
CASE @SortCol1
WHEN 'Foo' THEN t.Foo
WHEN 'Bar' THEN t.Bar
ELSE null
END as SortCol1,
CASE @SortCol2
WHEN 'Foo' THEN t.Foo
WHEN 'Bar' THEN t.Bar
ELSE...
How to Display Selected Item in Bootstrap Button Dropdown Title
...ied ur sample link but it is not working there, besides I need to grab the selected value as well to post to database later
– Suffii
Nov 18 '12 at 4:57
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Select where count of one field is greater than one
...clause, for aggregate result comparison.
Taking the query at face value:
SELECT *
FROM db.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparati...
Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
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How to Join to first row
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SELECT Orders.OrderNumber, LineItems.Quantity, LineItems.Description
FROM Orders
JOIN LineItems
ON LineItems.LineItemGUID =
(
SELECT TOP 1 LineItemGUID
FROM LineItems
W...
How do you open an SDF file (SQL Server Compact Edition)? [closed]
...t intuitive:
Open SQL Server Management Studio, or if it's running select File -> Connect Object Explorer...
In the Connect to Server dialog change Server type to SQL Server Compact Edition
From the Database file dropdown select < Browse for more...>
Open your SDF file.
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