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How do I remove blank elements from an array?
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511
There are many ways to do this, one is reject
noEmptyCities = cities.reject { |c| c.empty? }
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SQL how to increase or decrease one for a int column in one command
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To answer the first:
UPDATE Orders SET Quantity = Quantity + 1 WHERE ...
To answer the second:
There are several ways to do this. Since you did not specify a database, I will assume MySQL.
INSERT INTO table SET x=1, y=2 ON DUPLICATE KEY UPDATE x=x+1, y=y+2
REPLACE INTO table SET ...
delete_all vs destroy_all?
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edited May 23 '17 at 12:26
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answered Jul 14 '11 at 18:36
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What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
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581
They take up different amounts of space and they have different ranges of acceptable values.
He...
Using {} in a case statement. Why?
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The {} denotes a new block of scope.
Consider the following very contrived example:
switch (...
Gradle alternate to mvn install
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174
sdk/build.gradle:
apply plugin: "maven"
group = "foo"
version = "1.0"
example/build.gradle...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
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184
When you do len(df['column name']) you are just getting one number, namely the number of rows ...
How to silence output in a Bash script?
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189
If it outputs to stderr as well you'll want to silence that. You can do that by redirecting fi...
Syntax of for-loop in SQL Server
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216
T-SQL doesn't have a FOR loop, it has a WHILE loop
WHILE (Transact-SQL)
WHILE Boolean_expressi...