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Fast way to discover the row count of a table in PostgreSQL
.... Postgres may need to consider more rows than the limit anyway (like with ORDER BY something while it can't use an index, or with aggregate functions). Apart from that, only the limited number of rows from the subquery is processed.
– Erwin Brandstetter
Jun 17...
TortoiseSVN icons not showing up under Windows 7
...oiseCVS icons. This is because the overlay icons are used in alphabetical order. Again, at your own risk (editing the registry may blow up your computer, yada, yada, yada -- and if you are reading Stack Overflow and using Windows and haven't edited the registry, you are a rare beast indeed), feel f...
Disable output buffering
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A straight-forward way of using the flush keyword argument of Python 3 in order to always have unbuffered output is:
import functools
print = functools.partial(print, flush=True)
afterwards, print will always flush the output directly (except flush=False is given).
Note, (a) that this answers t...
In plain English, what does “git reset” do?
...ant to keep all the work you've done so you can fix it up and recommit. In order to commit, you'll have to add files to the index again (git add ...).
--soft doesn't touch the index or work tree. All your files are intact as with --mixed, but all the changes show up as changes to be committed with g...
Disable Visual Studio devenv solution save dialog
... do you have installed, if any? If more than one, did you install them in order of their version where Visual Studio 2012 was installed last?
– Rami A.
Jan 22 '13 at 1:19
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Entity Framework: “Store update, insert, or delete statement affected an unexpected number of rows (
... object you want to delete needs the PK set and the RowVersion Property in order to update it successfully! I was setting the rowVersion (timestamp) property, after I have attached the object to the respective DbSet, that's why it didn't work. Good job!
– Legends
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What happens to git commits created in a detached HEAD state?
... I thought so. Meh... it would have been a nice feature in order to reference rewritten/lost trees (for reviewed pull requests, in my case) [Maybe I should open a feature request!]. Anyway, thank you.
– Kamafeather
Jul 24 '18 at 15:01
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CharSequence VS String in Java?
...ple, look at the Java Collections Framework. If your API gives or takes an ordered collection of objects, declare your methods as using List rather than ArrayList, LinkedList, or any other 3rd-party implementation of List.
When writing a quick-and-dirty little method to be used only by your code i...
Why do you create a View in a database?
...base in which some of the entities were person, company, role, owner type, order, order detail, address and phone, where the person table stored both employees and contacts and the address and phone tables stored phone numbers for both persons and companies, and the development team were tasked with...
Postgres unique constraint vs index
...ion (not only on column) and define some other parameters (collation, sort order, NULLs placement).
You cannot add table constraint using partial index.
alter table master add column part_id integer;
create unique index master_partial_idx on master (part_id) where part_id is not null;
alter table...