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In Ruby, is there an Array method that combines 'select' and 'map'?
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I usually use map and compact together along with my selection criteria as a postfix if. compact gets rid of the nils.
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}
=> [3, 3, 3, nil, nil, nil]
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}.compact
=> ...
SELECT INTO Variable in MySQL DECLARE causes syntax error?
I´d like to SELECT a single value into a variable. I´d tried to following:
11 Answers
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Why is SELECT * considered harmful?
Why is SELECT * bad practice? Wouldn't it mean less code to change if you added a new column you wanted?
15 Answers
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Index of Currently Selected Row in DataGridView
It's that simple. How do I get the index of the currently selected Row of a DataGridView ? I don't want the Row object, I want the index (0 .. n).
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Insertion Sort vs. Selection Sort
I am trying to understand the differences between Insertion Sort and Selection Sort.
20 Answers
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How to declare a variable in MySQL?
...at has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BETWEEN @start AND @finish...
getting the ng-object selected with ng-change
Given the following select element
10 Answers
10
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How to select all instances of a variable and edit variable name in Sublime
If I select a variable (not just any string) in my code, all other instances of that variable get a stroke (white outline) around them:
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MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
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How to get multiple counts with one SQL query?
...tion. This is basically the same thing as a PIVOT function in some RDBMS:
SELECT distributor_id,
count(*) AS total,
sum(case when level = 'exec' then 1 else 0 end) AS ExecCount,
sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
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