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Why does Vim save files with a ~ extension?
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There is a table describing different behavior between combination of those switches: help backup-table. It turns out setting neither nobackup nor nowritebackup, but instead setting backupcopy=yes also solves the "jumping" problem. Thi...
Seeding the random number generator in Javascript
...334677,s)>>>0)/2**32;
These LCG values are from: P. L'Ecuyer: A table of Linear Congruential Generators of different sizes and good lattice structure, April 30 1997.
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Merging dictionaries in C#
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Dictionary<String, String> allTables = new Dictionary<String, String>();
allTables = tables1.Union(tables2).ToDictionary(pair => pair.Key, pair => pair.Value);
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PostgreSQL return result set as JSON array?
...scribes how to generate a JSON object, with each key being a column in the table and each value being an array of the values of the column. It's the result that looks like this:
{"a":[1,2,3], "b":["value1","value2","value3"]}
9.5 and up
We can leverage the json_build_object function:
SELECT
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Is there a point to minifying PHP?
...o improve performance... after performing benchmarking and profiling and establishing that caching itself will be the best possible performance gain.
– Charles
Nov 2 '10 at 16:58
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ActiveRecord.find(array_of_ids), preserving order
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for me chaining don't work. Here tables name should be added before id:text like this: ["position((',' || somethings.id::text || ',') in ?)", ids.join(',') + ','] full version that worked for me: scope :for_ids_with_order, ->(ids) { order = sanitize_...
Creating a copy of a database in PostgreSQL [closed]
...rday it worked, now random unique constrain are violated. Note: I drop all table to receiver db.
– gunzapper
Apr 1 '16 at 10:45
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JPA eager fetch does not join
...nd JOIN are two extremes and SUBSELECT falls in between. One can choose suitable strategy based on her/his domain model.
By default SELECT is used by both JPA/EclipseLink and Hibernate. This can be overridden by using:
@Fetch(FetchMode.JOIN)
@Fetch(FetchMode.SUBSELECT)
in Hibernate. It also all...
Which is more efficient, a for-each loop, or an iterator?
...n invokeInterface virtual call (go through all the classes, then do method table lookup before the jump).
the implementation of the iterator has to do at least 2 fields lookup in order to make hasNext() call figure the value: #1 get current count and #2 get total count
inside the body loop, there is...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...wouldn't apply to (e.g. "insert").
Use help map-modes will show you a few tables that explain how to control which modes the mapping applies to.
Mode letters:
n: normal only
v: visual and select
o: operator-pending
x: visual only
s: select only
i: insert
c: command-line
l: insert, command-line, ...