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Why is lazy evaluation useful?
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@Viclib A selection algorithm for finding the top k elements out of n is O(n + k log k). When you implement quicksort in a lazy language, and only evaluate it far enough to determine the first k elements (stopping evaluation after), i...
How do I force Postgres to use a particular index?
...d, client_id, date, and description. You want to run the following query:
SELECT client_id, SUM(amount)
FROM transactions
WHERE date >= 'yesterday'::timestamp AND date < 'today'::timestamp AND
description = 'Refund'
GROUP BY client_id
PostgreSQL may choose to use the index transaction...
Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...shion. The "best" way to break is by compilation error. For example if you SELECT * somewhere, the addition of a column could fail to compile. The next best way to fail would be a run time error. It's worse because your users may see it, but it still gives you a nice warning that you've broken somet...
How can a LEFT OUTER JOIN return more records than exist in the left table?
...FT table, then you have no need to perform a JOIN at all and can just do a SELECT directly from the LEFT table.
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What are the obj and bin folders (created by Visual Studio) used for?
... a compile in your project's Properties. You can also change the names and selected options for your build configurations.
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List all indexes on ElasticSearch server?
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you can also select and order columns adding e.g. &h=health,index as well as sort with &s=health:desc
– Georg Engel
Dec 18 '18 at 19:33
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What is the benefit of using “SET XACT_ABORT ON” in a stored procedure?
...h
declare @error int, @message varchar(4000), @xstate int;
select @error = ERROR_NUMBER(), @message = ERROR_MESSAGE(), @xstate = XACT_STATE();
if @xstate = -1
rollback;
if @xstate = 1 and @trancount = 0
rollback
if @xstate = 1 and @tran...
Replacing .NET WebBrowser control with a better browser, like Chrome?
...mulationCode = BrowserEmulationVersion.Version11
Else
Select Case ieVersion
Case 10
emulationCode = BrowserEmulationVersion.Version10
Case 9
emulationCode = BrowserEmulationVersion.Version9
C...
difference between primary key and unique key
...ey, unique key, etc are collectively called as Candidate Key.
However, DBA selected a key from candidate key for searching records is called Primary key.
Difference between Primary Key and Unique key
1. Behavior: Primary Key is used to identify a row (record) in a table, whereas Unique-key is to...
Disable spell checking on IntelliJ IDEA
...u can either:
Disable spell checking entirely, or
Disable spell checking selectively (e.g. just the code), but enable for some others (e.g. comments).
I'm on MacOS Webstorm (version 2016.1.2). First thing first, go to the "Inspection" pane like this...
Webstorm -> Preferences -> search fo...