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How to use GROUP BY to concatenate strings in SQL Server?
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18 Answers
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How do write IF ELSE statement in a MySQL query
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150
You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case wh...
iOS 7 TableView like in Settings App on iPad
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15 Answers
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undefined method `source_index' for Gem:Module (NoMethodError)
...to this problem myself while trying to upgrade an older Rails app from REE 1.8.7 to 1.9.3-p385. Oddly, Ruby 1.9.3-p327 works just fine. What it came down to was ruby-1.9.3-p385 had installed RubyGems version 2.0.2 for me, and 1.9.3-p327 has RubyGems v1.8.23 installed.
Gem.source_index has been depr...
Ukkonen's suffix tree algorithm in plain English
...se, each
edge carries a string label of arbitrary length, but takes only O(1)
space (two pointers).
Basic principle
I would like to first demonstrate how to create the suffix tree of a
particularly simple string, a string with no repeated characters:
abc
The algorithm works in steps, from left...
MySQL: @variable vs. variable. What's the difference?
...nitialize this variable with a SET statement or inside a query:
SET @var = 1
SELECT @var2 := 2
When you develop a stored procedure in MySQL, you can pass the input parameters and declare the local variables:
DELIMITER //
CREATE PROCEDURE prc_test (var INT)
BEGIN
DECLARE var2 INT;
SET var...
List of zeros in python [duplicate]
...zeros? I want to be able to create a zeros list for each int in range(10)
8 Answers
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How do you know when to use fold-left and when to use fold-right?
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105
You can transfer a fold into an infix operator notation (writing in between):
This example fo...