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How to speed up insertion performance in PostgreSQL
...n the PostgreSQL manual, depesz's excellent-as-usual article on the topic, and this SO question.
(Note that this answer is about bulk-loading data into an existing DB or to create a new one. If you're interested DB restore performance with pg_restore or psql execution of pg_dump output, much of thi...
How do I add a foreign key to an existing SQLite table?
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SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as follows:
CREATE TABLE child (
id INTEGER PRIMARY KEY,
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How to share Eclipse configuration over different workspaces
...es. (like at home, laptop, in office, etc.). How could I share the Eclipse and project configuration pragmatically between multiple computers? Should I version control them, or is there any easier way to do this?
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SQL Joins Vs SQL Subqueries (Performance)?
...PECT the first query to be quicker, mainly because you have an equivalence and an explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may va...
Making heatmap from pandas DataFrame
I have a dataframe generated from Python's Pandas package. How can I generate heatmap using DataFrame from pandas package.
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html (+css): denoting a preferred place for a line break
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By using
span.avoidwrap { display:inline-block; }
and wrapping the text I want to be kept together in
<span class="avoidwrap"> Text </span>
it will wrap first in preferred blocks and then in smaller fragments as needed.
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When should std::move be used on a function return value? [duplicate]
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met save for the fact that the source object is a function parameter,
and the object to be copied is designated by an lvalue, overload
resolution to select the constructor for the copy is first performed as
if the object were designated by an rvalue.
return foo; is a case of NRVO, so cop...
How to turn on/off ReactJS 'development mode'?
...he other answer assumes you are using external pre-built files from react, and while correct that is not how most folks are going to or should consume React as a package. Moreover, at this point most every React library and package also relies on the same convention to toggle dev time helpers off du...
Regex to check whether a string contains only numbers [duplicate]
I get false on both "123" and "123f" . I would like to check if the hash only contains numbers. Did I miss something?
21...
Understanding offsetWidth, clientWidth, scrollWidth and -Height, respectively
... on StackOverflow regarding offsetWidth / clientWidth / scrollWidth (and -Height , respectively), but none give comprehensive explanation of what those values are.
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