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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
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21 Answers
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Plot two graphs in same plot in R
I would like to plot y1 and y2 in the same plot.
16 Answers
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How to find a min/max with Ruby
I want to use min(5,10) , or Math.max(4,7) . Are there functions to this effect in Ruby?
6 Answers
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Get all column names of a DataTable into string array using (LINQ/Predicate)
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edited Sep 19 '15 at 8:48
answered Feb 17 '11 at 7:54
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Understanding keystore, certificates and alias
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1 Answer
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Escape single quote character for use in an SQLite query
...abases expect it that way), so it would be :
INSERT INTO table_name (field1, field2) VALUES (123, 'Hello there''s');
Relevant quote from the documentation:
A string constant is formed by enclosing the string in single quotes ('). A single quote within the string can be encoded by putting two ...
git -> show list of files changed in recent commits in a specific directory
...es -- for details see the online manual at http://svnbook.red-bean.com/en/1.7/svn.ref.svn.c.log.html
4 Answers
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Entity Framework: There is already an open DataReader associated with this Command
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PostgreSQL DISTINCT ON with different ORDER BY
...approaches:
The general solution that should work in most DBMSs:
SELECT t1.* FROM purchases t1
JOIN (
SELECT address_id, max(purchased_at) max_purchased_at
FROM purchases
WHERE product_id = 1
GROUP BY address_id
) t2
ON t1.address_id = t2.address_id AND t1.purchased_at = t2.max_pur...