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How do you run a single query through mysql from the command line?
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mysql -u <user> -p -e "select * from schema.table"
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How to set top-left alignment for UILabel for iOS application?
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Works like a charm, even in a UITableViewCell with reuse.
– alex.bour
Jun 10 '16 at 8:53
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Sorting arrays in NumPy by column
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You can sort on multiple columns as per Steve Tjoa's method by using a stable sort like mergesort and sorting the indices from the least significant to the most significant columns:
a = a[a[:,2].argsort()] # First sort doesn't need to be stable.
a = a[a[:,1].argsort(kind='mergesort')]
a = a[a[:,...
“Keep Me Logged In” - the best approach
...in, generate a large (128 to 256 bit) random token. Add that to a database table which maps the token to the userid, and then send it to the client in the cookie.
What if the attacker guesses the random token of another user?
Well, let's do some math here. We're generating a 128 bit random token....
Large Object Heap Fragmentation
...is is a very interesting lead, thanks. Completely forgot about the intern table. I know one of our developers is a keen interner so this is definitely something I shall investigate.
– Paul Ruane
Mar 27 '09 at 10:34
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Rails migrations: self.up and self.down versus change
... you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation the methods currently supported from the change method).
But pay attention becaus...
to drawRect or not to drawRect (when should one use drawRect/Core Graphics vs subviews/images and wh
...it would be more complicated.
The general workflow should be to build the tableviews with subviews. Use Instruments to measure the frame rate on the oldest hardware your app will support. If you can't get 60fps, drop down to CoreGraphics. When you've done this for a while, you get a sense for when ...
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...at is generated is sub-optimal.
For example, if you send SELECT *
FROM table WHERE id BETWEEN 1 AND
99999999, the DBMS may select a
full-table scan instead of an index
scan because you're grabbing every row
in the table (so sayeth the
statistics). If this is the cached
version, then ...
SQL Server: Examples of PIVOTing String data
...on will work on text as well as numbers. This query will only require the table to be scanned once.
SELECT Action,
MAX( CASE data WHEN 'View' THEN data ELSE '' END ) ViewCol,
MAX( CASE data WHEN 'Edit' THEN data ELSE '' END ) EditCol
FROM t
GROUP BY Action
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How do I drop a foreign key in SQL Server?
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Try
alter table company drop constraint Company_CountryID_FK
alter table company drop column CountryID
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