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How do I delete a fixed number of rows with sorting in PostgreSQL?
...DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the row version very quickly, a row's ctid will change if it is...
How to remove/ignore :hover css style on touch devices
...r for them.
If you're able to use an internet duct-tape language such as PHP or Ruby, you can check the user string of the device requesting a page, and simply serve the same content but with a <link rel="mobile.css" /> instead of the normal style.
User strings have identifying information...
How to compare if two structs, slices or maps are equal?
...imple integers. Are slices equal if they contain same elements in the same order? But what if their capacities differ? Etc.
– justinas
Jul 12 '14 at 15:45
...
Backbone.js: `extend` undefined?
...arification from @tjorriemorrie:
I had underscore, but loaded in the wrong order, first load underscore (guess that is what 'dependency' means :)
Further Clarification just in case this isn't obvious. The order that things are loaded in JavaScript relates to the order the show up on the page. T...
What is recursion and when should I use it?
... I am using your explanation in an article I am writing for PHP Master though I can't attribute it to you. Hope you don't mind.
– frostymarvelous
How to delete an item in a list if it exists?
...ing)
The removemethod will remove only the first occurrence of thing, in order to remove all occurrences you can use while instead of if.
while thing in some_list: some_list.remove(thing)
Simple enough, probably my choice.for small lists (can't resist one-liners)
2) Duck-typed, EAFP styl...
UPDATE multiple tables in MySQL using LEFT JOIN
...
See the article in my blog for performance details:
Finding incomplete orders: performance of LEFT JOIN compared to NOT IN
Unfortunately, MySQL does not allow using the target table in a subquery in an UPDATE statement, that's why you'll need to stick to less efficient LEFT JOIN syntax.
...
Idiomatic way to convert an InputStream to a String in Scala
...
This is potentially an order of magnitude faster than scala.io.Source in Scala 2.11.7. I wrote a really basic benchmark of it and most of the time, it was about 5% faster for large files (test was ~35 MB text file) all the way up to 2,800% faster f...
Condition within JOIN or WHERE
...sider these two queries:
SELECT *
FROM dbo.Customers AS CUS
LEFT JOIN dbo.Orders AS ORD
ON CUS.CustomerID = ORD.CustomerID
WHERE ORD.OrderDate >'20090515'
SELECT *
FROM dbo.Customers AS CUS
LEFT JOIN dbo.Orders AS ORD
ON CUS.CustomerID = ORD.CustomerID
AND ORD.OrderDate >'20090515'
The f...
cannot convert data (type interface {}) to type string: need type assertion
...Even if i is an interface type, []i is not interface type. As a result, in order to convert []i to its value type, we have to do it individually:
// var items []i
for _, item := range items {
value, ok := item.(T)
dosomethingWith(value)
}
Performance
As for performance, it can be slower ...