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How to add to an existing hash in Ruby
...ash in Ruby, I'm in the process of working through Apress' Beginning Ruby and have just finished the hashes chapter.
7 Ans...
Dynamic Sorting within SQL Stored Procedures
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Yeah, it's a pain, and the way you're doing it looks similar to what I do:
order by
case when @SortExpr = 'CustomerName' and @SortDir = 'ASC'
then CustomerName end asc,
case when @SortExpr = 'CustomerName' and @SortDir = 'DESC'
then...
What is the difference between float and double?
I've read about the difference between double precision and single precision. However, in most cases, float and double seem to be interchangeable, i.e. using one or the other does not seem to affect the results. Is this really the case? When are floats and doubles interchangeable? What are the d...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
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So I guess it is safer to define a variable with the result of that command as your empty sha1 tree (instead of relying of a "well known value").
Note: Git 2.25.1 (Feb. 2020) proposes in commit 9c8a294:
empty_tree=$(git mktree </dev/null)
# Windows:
git mktree <NUL
And adds:
As a hi...
List all sequences in a Postgres db 8.1 with SQL
...mmunity wiki
2 revs, 2 users 92%Anand Chitipothu
5
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Maven: how to do parallel builds?
... does not invoke maven externally.
– Thorbjørn Ravn Andersen
Oct 14 '15 at 14:03
add a comment
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Parsing JSON using Json.net
... JSON using the JSon.Net library. The documentation seems a little sparse and I'm confused as to how to accomplish what I need. Here is the format for the JSON I need to parse through.
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How do I drop a function if it already exists?
...ion with a check to see if it already exists? If it exists, I want to drop and re-create it.
11 Answers
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How do you use script variables in psql?
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Postgres variables are created through the \set command, for example ...
\set myvariable value
... and can then be substituted, for example, as ...
SELECT * FROM :myvariable.table1;
... or ...
SELECT * FROM table1 WHERE :myvariable IS NULL;
edit: As of psql 9.1, varia...
Flatten an Array of Arrays in Swift
Is there a counterpart in Swift to flatten in Scala, Xtend, Groovy, Ruby and co?
14 Answers
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