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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ions:
Individual insert/update operations in a retry loop; or
Locking the table and doing batch merge
Individual row retry loop
Using individual row upserts in a retry loop is the reasonable option if you want many connections concurrently trying to perform inserts.
The PostgreSQL documentation co...
What's the fastest way to merge/join data.frames in R?
... posted in the question, it might appear that indexes were used on the two tables but, in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts for why its so slow. The idea of sqldf is that the data frames in your R session constitute th...
What is the closest thing Windows has to fork()?
...
Cygwin has fully featured fork() on Windows. Thus if using Cygwin is acceptable for you, then the problem is solved in the case performance is not an issue.
Otherwise you can take a look at how Cygwin implements fork(). From a quite old Cygwin's architecture doc:
5.6. Process Creation
The f...
MySQL pagination without double-querying?
... this tickles that affects ORDER BY queries making it much slower on large tables than the naive approach of two queries.
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Code coverage with Mocha
...text mocha"
}
}
Run
Now run your tests
npm test
and you will see a table like this in your console, just after your tests output:
Customization
Html report
Just use
nyc --reporter=html
instead of text. Now it will produce a report inside ./coverage/index.html.
Report formats
Istanb...
How do I rename a column in a SQLite database table?
I would need to rename a few columns in some tables in a SQLite database.
I know that a similar question has been asked on stackoverflow previously, but it was for SQL in general, and the case of SQLite was not mentioned.
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How to insert a SQLite record with a datetime set to 'now' in Android application?
Say, we have a table created as:
10 Answers
10
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How do I view the list of functions a Linux shared library is exporting?
...at must be loaded from other shared objects have a U. Note that the symbol table does not include just functions, but exported variables as well.
See the nm manual page for more information.
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Best way to represent a Grid or Table in AngularJS with Bootstrap 3? [closed]
I am creating an App with AngularJS and Bootstrap 3. I want to show a table/grid with thousands of rows. What is the best available control for AngularJS & Bootstrap with features like Sorting, Searching, Pagination etc.
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
I'm coming to Postgres from Oracle and looking for a way to find the table and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer.
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